Dave Hill’s 2006 Z06 stunned everyone with its stiffer than stock aluminum frame.
Dateline: 1.17.20 – Graphics by K. Scott Teeters, Images from GM archives: Corvette fans have been frustrated for years with Chevrolet’s evolutionary Corvettes. The “pie-in-the-sky” mid-engine Corvette has been around since the 1960s and anything less was evolutionary. The pending C8 aside, the C5 was the most revolutionary Corvette; because of the hydroformed steel perimeter frame, center backbone, all-aluminum LS1 fuel-injected engine, and transaxle. The C5 was the most solid Corvette ever offered and allowed engineers to vastly improve the basic suspension, the Z51, and the Z06. The racing C5-R won its class at Daytona in 2001 and 2003; won its class at Sebring in 2002, 2003, and 2004, and won its class at Le Mans in 2001, 2002, and 2004. This never would have happened without the superior basic C5 chassis. Dave Hill’s team got the C5’s chassis design so right that by 1999 they determined that a C6 needed to be started.
Whereas the C5 structure was revolutionary, the C6 was evolutionary. While the C6 chassis is different from the C5, it is essentially the same hydroformed steel perimeter frame with a center backbone, with the engine, torque tube, and transaxle all as stress members of the overall structure.
Photo: GM Archives
Let’s start with the basic C6 chassis. The chassis has a 1.2-inch longer wheelbase of 105.7-inches, but the overall length is 5.1-inches shorter than the C5 chassis. To achieve this, engineers shortened the frame rails 2.4-inches and changed the tube-formed front bumper beam to a unit made with two channels welded together to save 2/3s of an inch. The shorter frame with less overhang on the body achieved a total of 5.1-inches of length on the C6, over that of the C5. The shorter frame also increased the torsional stiffness. And to reduce squeaks, rattles, and vibrations, high-strength steel braces were added to the frame to improve structural rigidity.
Weight savings were picked up by using extruded aluminum beams in the interior instead of the cast aluminum beams from the C5. The instrument panel has additional brackets for the beam under the dashboard. Side-impact beams were made of aluminum and saved 4.5-pounds, plus the doors do not have traditional latch and lock mechanisms. Aluminum braces were used through the structure to improve crash performance. The front skid-bar in front of the radiator is also aluminum. An aluminum panel that saved 1-pound and increased stiffness replaced the steel driveline panel under the driveline torque tube. To increase upper rigidity, the windshield frame has extra gussets. And the trunk uses lightweight plastic braces. Corvette systems engineer Ed Moss said, “We are making it (the C6) smaller, lighter, but stiffer.”
The issue of stiffness in high-powered sports cars with wide tires cannot be under-estimated. Increased grip, torque, and horsepower will put tremendous added stress to a performance car’s structure. Imagine what would happen if a LT5 engine and big tires were applied to a stock C1 chassis. The C5 1999-2000 Corvette Hardtop, with its bolted and bonded hardtop increased the overall structural stiffness by 12-percent, enough to make it an excellent base to build the Z06 upon. The basic C6 platform offered a significant improvement in stiffness that made it an excellent platform to build the Grand Sport that used Z06 suspension parts and wide tires. Without any increase in power, the Grand Sport was a better Corvette. Stiffness matters.
Photo: GM Archives
While the C6’s suspension is similar to the C5’s, there are no carryover parts. The basic design of the short-long A-arms, transverse composite leaf springs independent suspension is the same. The control arms, springs, dampers, bushing, sway bars, and steering gear are all completely redesigned. New hub knuckles and dampers allow for greater suspension travel thanks to improved clearance. One issue with C5s was road noise and twitchiness on rough roads. To improve handling and ride, steering geometry and the progressive rates of the composite springs were improved.
Like the C5 the C6 offered customers three levels of suspension performance. Chevrolet calls the basic C6 suspension, “tuned for balance, ride comfort, and precise handling.” This is for the customer that wants a Corvette because they like “driving a Vette” with 400-horsepower on tap when they want a brief thrill, but aren’t interested in exploring the limits of tire grip.
Photo: GM Archives
The F55 Magnetic Selective Ride Control was a $1,695 option with some amazing technology. Magnetorheological dampers use metal-infused fluid that controls the viscosity of the fluid with a magnetic field created by an electromagnet. This semi-active suspension adjusts the fluid via a computed to adjust damping rates based on road surfaces down to the millisecond. The active handling and antilock systems were smarter and less intrusive.
And for the enthusiast that doesn’t want to go for the serious big gun Z06, but wants the most from their base model Corvette, there was the $1,495 Z51 Performance Package. The F51 option has been around since 1984 with a starting price of $600 with prices fluctuating through to 1990. Then from 1991 to 1995 Chevrolet offered the $2,045 Z07 Adjustable Suspension Package. The Z51 option was back in 1996 but consisted only of stiffer springs and stabilizer bars for $350 from 1996 to 2003, then $395 in 2003 and 2004.
Photo: GM Archives
The Z51 was part of the C6 lineup from 2005 to 2009 and was a whole different animal. Costing $1,495 in 2005, then $1,695 from 2006 to 2009, the Z51 package was the most comprehensive Z51 package ever offered, consisting of; higher rate springs and shocks; larger sway bars; larger cross-drilled rotors – 13.5-inch diameter on the front and larger 13-inch diameter on the rear; coolers for the engine oil, transmission, and power steering; higher-grip Goodyear EMT tires; revised gear ratios for the 6-speed cars.
Photo: GM Archives
An interregnal part of the overall objective of a smaller, lighter, and stiffer C6 was the body. For the body part of the C6, designers wanted to improve the fit of the body panels and reduce weight. For the broad flat parts, such as the hood, doors, trunk lid and tonneau cover on the convertible, SMC – Sheet Molded Compound was used. This is a fiberglass mixed with resin that is compressed into a mold, with a chemical reaction and the heat from the compression curing the part. For more complex shapes, such as the front grille and the rear fascia, PRIM – Polyurethane-Material Reinforced-Reaction Injection Molding was used. The removable roof panel was made from Polycarbonate, either transparent or painted.
Photo: GM Archives
But the major breakthrough for the C6 chassis was the all-aluminum chassis for the Z06 and the ZR1. The basic chassis design is the same except that the hydroformed side rails are made of 4-mm 5745 aluminum alloy. The standard C6 steel frame thickness was 3-mm and weighs 502-pounds while the aluminum Z06 frame weighs 392-pounds; that’s 110-pounds lighter, or 22.5-percent lighter. The Z06 frame is 50-percent stronger in torsional and bending stiffness. The Metalso Metal Fabricator, in Hopkinsville, Kentucky manufactured the aluminum frames and then shipped them to the Corvette Bowling Green assembly plant. The engine cradle and fixed-roof panel are magnesium, and the floorboards were carbon fiber.
Everything tends to move upward in the world of Corvettes. When the Z06 debuted in 2006, no one imagined that the C7 base Corvette would ride on a C6 Z06-like chassis.
The C5 Corvette’s Momemtim Chassis took the Corvette to a whole new level and paved the way for the C5-R Corvette
Dateline: 1-16-20 – Graphics by K. Scott Teeters, Images from GM archives:Structure is everything. Lessons learned from the C5, C6, and C7 Corvettes is that the stiffer the chassis, the better the suspension can be tuned for improved handling. The C1 to C4 chassis’ were fine for their day, but compared to the modern Corvettes, they leave a lot to be desired, especially if bigger tires and more horsepower is applied. The issue of structure is not new; look at what the Greenwood brothers were doing with the chassis of their widebody IMSA Corvettes in the 1970s. The NASCAR cars of the 1970s had fortress-like cages welded to their frames; but you can’t live with structures like that for streetcars. The arrival of the C5 was a quantum leap in terms of structure.
Image: GM Archives, 1997 Corvette Brochure
Joe Spielman ran GM’s Midsize Car Division in 1992 and was responsible for forty-percent of the engineering and manufacturing of GM’s auto production. It was a bad time for GM and despite the Corvette’s iconic status; its future was in jeopardy. Spielman created the “Decision Makers” that included himself, Carlisle Davis, John Cafaro, and Dave McLellan. Three possible formats for the C5 Corvette were created. The first format was the “Momentum Architecture” that featured a stiff backbone, front-engine, rear transmission, and an evolutionary body style. The second format was the “Mid-Engine”, favored by McLellan and GM President Jack Smith. The 1990 CERV III wasn’t just a dream car, it was built with manufacturing in mind, but was going to be complex and expensive. The third format was “Stiffer and Lighter”. This would be the least expensive and was a stiffer, lighter version of the C4. Fortunately, the team went with the “Momentum Architecture”.
The problem was money. When Dave Hill took over, as Corvette chief engineer in November 1992, his 1993 development budget was just $12 million. The estimated total cost to design and develop the C5 was originally $250 million and was cut back to $150 million; GM was in financial trouble and was cutting everything. But Chevrolet general manager Jim Perkins saved the Corvette by juggling an extra $1.2 million so that Hill could build a demonstration car. Another consideration Perkins wanted to see was a “Billy Bob” no-frills concept. Hill’s demonstration Corvette would become the CERV IV, with a manual transmission. Later Hill build an automatic version called the CERV IVb. The “Billy Bob” concept wasn’t developed until 1998 and became the 1999 Hardtop, that later became the now-legendary Z06.
The CERV IV was a true stealth development car. The chassis had the backbone structure of the proposed “Momentum Architecture” plan, but was clothed in a C4 body so that Hill and his team could drive the car on public roads, as well as the Proving Grounds in Michigan and Arizona. To the public it was just another C4 Corvette. Hill’s objectives for the CERV IV were to; prove to GM’s president Jack Smith that his team could reinvent the car, as well as the building process. When Hill took people for test-drives, they said, “This is like no Corvette we ever felt!” Hill’s plan worked, he got his C5 development budget up to $241 million, and set his team to work.
Image: https://www.corvettes.nl
Hill wanted the C5 to be able to do everything as well as, or better than the C4. The C4 had a 350-mile range; Hill wanted 370 for the C5. The solution to the fuel range was a blessing because instead of one tank mounted on top of the rear of the frame, the C5 has two tank placed low on each side of the transaxle. This also helped lower the C5’s center of gravity. Hill wanted a coefficient of drag of .29, the lowest of any production car at that time, so he had to lean on designer John Carfaro.
But the piece de resistance of the C5’s new structure was its hydroformed frame. The first mass-produced automotive application of Hydroforming was for the instrument panel support beam in a 1990 Chrysler mini van. The 1997 C5 Corvette was the first mass-produced automobile to use this manufacturing technique on a major structural component. The frames of all pervious Corvettes were made from sheet steel, bent to form a box section. The box sections were then welded together to form the side rails and cross members. Hydroforming creates complex shapes that are stronger, lighter, and more rigid. After engineers designed the shape of the C5’s frame rails, sheet steel was rolled into a tube, laser-welded, and bent into the basic shape of the frame rail. The shaped tube was then placed inside a form and sealed. Water was then pumped into the tube at 7,000 psi that inflated the steel into the shape. The finished side rail was one, 13-foot long piece, instead of many boxed pieces all welded together. The crossmembers and attachment brackets, (36 pieces in total) were welded by robotic and human welders. Convertibles have 33 parts, one extra for the tonneau cover latch.
https://www.corvettes.nl
The second major structural component on the new C5 was the longitudinal center tunnel backbone. This kind of construction had then only been seen on exotic supercars and racecars. The center backbone creates the driveshaft tunnel and locks the front and rear of the frame together. The C4 designers had a long driveline support torque bar that bolted to the end of the transmission and the rear differential, whereas the designers of the C5 created an enclosed torque tube that bolted to the back of the bellhousing and the front of the transaxle, with a lightweight Metal Matrix Composite (MMC) driveshaft. The torque tube that connects the engine with the transaxle, was then bolted to the frame. Combined with the center backbone, the C5’s chassis structure is four times as stiff as the C4. This was an amazing accomplishment for a mass-produced sportscar.
With the strongest structure ever created for a Corvette, Hill’s suspension engineers were better able to design components to fine tune wheel control. Now the suspension didn’t have to compensate for a flexing structure. The selection of springs, dampers, anti-roll bars and bushings can be more accurate. The C4 suspension was very good and is today used often on street rods. The C5 went to the next level with double A-arms on all four corners of the independent suspension. The new aluminum suspension components are made using the then-new process of casting-and-forging to create lighter, stronger parts.
The C5 came with three levels of suspension. The standard FE1 was for basic driving and used specifically selected fiberglass composite leaf springs, shocks, sway bars, and bushings. The $350 optional Z51 suspension had stiffer springs, shocks, and larger-diameter sway bars. Active suspension options had been around since 1989; the new C5 offered the latest version of the F45 Selective Real Time Damping for $1,695. The C5’s basic dimensions tell us a lot. The C5 is 179.4-inches, 1.1-inches longer than the C4; 73.6-inches wide, 2.9-inches wider than the C4; 47.8-inches in height, 1.5-inches taller than the C4; 104.5-inch wheelbase, 8.3-inches longer than the C4; and 3,221-pounds, 77-pounds lighter than the C4. Wider, lighter, stiffer, with an all-aluminum engine, transaxle, and over 1,200 fewer parts, the C5 was the most revolutionary Corvette to date. – Scott
After 20 years of use, the C2/C3 Corvette chassis was finally replaced with a strong, lightweight, vastly improved chassis and structure.
Dateline: 8.9.19 – Illustrations from GM Archives, Grahics by K. Scott Teeters –The C2/C3 chassis had an amazing 20-year production run. When Dave McLellan took over as Corvette’s chief engineer in 1975, the Corvette was overdue for a redesign. The only good thing about the 1970s was that Corvettes sold very well. On January 22, 1979 McLellan received approval to start designing the C4 Corvette.
One of the C3’s endearing features was the T-top roof. The design wasn’t just for aesthetics; the T-bar connected the A-pillar windshield frame to the B-pillar frame “roll bar” and provided significant structural stiffness. The initial design of the C4 had a T-bar connecting the A and B-pillars, but with a one-piece, roof panel. It wasn’t until the first prototype was built in 1981, when Chevrolet general manager Lloyd Reuss made the decision to eliminate the T-bar to open up the cockpit. This single decision impacted the C4 design such that the biggest complaint about C4s is the tall side frame sills that make ingress and egress challenging. To compensate for the lack of the important T-bar, the side frame sills had to be made extra tall. As the years rolled by, C4s, especially the convertibles, took heat for not being as stiff as their competitors. Those two elements, plus the fact that progressive Corvettes kept getting better and better, are part of the reason why C4s are today the least desirable of all Corvettes.
McLellan’s engineers had two overriding design elements; first, they wanted a lower overall height; and second; they wanted more ground clearance. McLellan’s team started placing the big pieces in a process they called, “stacking”. Starting at the ground level, the engine had to be lower to improve forward visibility. Previous Corvettes had been two-part cars; a body bolted on to a chassis. But the C4 was a three-piece car, which included, a chassis, a birdcage, and a body. This created a more integrated body and stronger configuration.
The C4’s parameter frame was built from 18 pieces of stamped and boxed high-strength steel that included the tall side sills, the front sides, the rear sides, four crossmembers and braces. All of the pieces were put together in a jig and welded together. The birdcage section included the forward door jams, the dash crossmember, the A-pillar, the rear section of the floor pan, and the B-pillar. The completed birdcage was then welded to the parameter frame. An aluminized steel engine and front suspension cradle positioned the engines and provided mounting points for the front suspension. The rear section of the frame was aluminum and provided mounting points for the rear suspension and rear bumper.
Unlike the previous chassis’ that had the engine, transmission, and suspension simply bolted to the frame, the C4 used a steel driveline support that was bolted to the rear of the transmission and connected to the rear differential that housed the driveshaft. By doing this, all of the components became stress members of the chassis structure.
Thanks to the C4 Corvette’s unique clamshell hood, Corvette owners got to see more of their front suspension than ever. Gone were the days of heavy stamped steel upper and lower A-arms. The C4’s front A-arms and spindles were slender, computer-designed forged aluminum. The C4 suspension used composite leaf springs on the front and rear suspension. Don’t let the term “leaf spring” throw you. These are computer-engineered, high-tech, lightweight suspension parts. A composite fiberglass monoleaf spring was first used in 1981.
To download a PDF version of the 1984 Corvette brochure, CLICK HERE.
To download a PDF version of the 1984 Corvette brochure, CLICK HERE.
C4’s multi-link rear suspension eliminated the C2/C3 rear end “squat” upon hard acceleration. This setup uses upper and lower control rods that connect the wheel bearing yolks to brackets mounted to the vertical section of the of the rear of the frame. Each bearing yolk has support rods that tie it to the rear differential. Today when we look at C4 Corvettes, especially tired old examples, the frame and suspension looks somewhat crude and outdated. However, C4 suspensions are regularly harvested from salvage yards, cleaned up, and refreshed for street rods.
From the perspective of the C4 Corvette’s November 30, December 1, 1982 press debut, the car was a total “WOW!” The cover story of the March 1983 issue of Road & Track was “Corvette Spectacular!” The debut wasn’t unlike the debut of the C6 and C7 Grand Sport Corvettes, in that with virtually the same horsepower, teamed with a much better suspension (the Z06 on the C6 and C7 GS), the car is vastly improved. Automotive journalists were blown away by how tight and solid the new C4 was. But it was the skidpad performance that astounded everyone. Z51 examples had no trouble hitting 0.95g on the pad, and one Z51 with slightly wider front tires scored a 1.01g! Ferrari’s $80,000 512 Boxer could only generate 0.86g, and Richard Petty’s Grand National Stock Car scored 1.04g. The March 1983 issue of Popular Mechanics proclaimed, “1983 Corvette: Best American Car Ever!”
Bowling Green started the 1984 season early and consequently racked up the second-best ever sales season with 51,547 Corvettes sold. Media hype totally stoked Corvette fans for the Z51, such that 50.4-percent of all 1984 Corvettes were ordered with the $600 Z51 option. Then reality set in. On real roads the ride was for many unbearable, in fact, many owners of regular 1984 Corvettes weren’t happy with the ride quality. Corvette engineers acknowledged that they had “over-done-it” on the suspension.
For 1985 engineers softened the front springs by 26-percent in the front and 25-percent in the rear. Z51 springs were softened 16-percent in the front and 25-percent in the rear with larger stabilizer bars. 1985 also saw the return of a full-fledged fuel-injection system with the introduction of the L98 that had a 25-horsepower bump that made the Corvette, according to Car and Driver, “The Fastest Car In America”. It was also the beginning of a three-year romp by Corvettes in the SCCA Showroom Stock Series. Corvettes so dominated the series they were kicked out in 1988 and Porsche bought a C4 Corvette to learn why the car was so fast.
But as power started to nudge up and tires got wider, the inherent design flaw with the C4’s lack of a T-bar was more obvious, especially on the convertibles; even with a bolt-on X-brace on the bottom of the chassis that raised the ride height 10mm. Since there are so many C4 Corvettes out there that few want, unless the car is a special edition or a pace car, you can do almost anything to a C4 and never get any heat. I learned from the C4 forums that many C4 owners that are hot rodding their cars use the factory X-brace and frame torsion rods to stiffen the structure of their car. Makes sense if you are adding a lot more power and bigger tires.
The C4 had a long run of 13-years. Towards the end of McLellan’s tenure as Chief Engineer in the early 1990s, he pushed for the C5, but GM was having money trouble and was in no mood for a new Corvette. In fact, they were considering eliminating the Corvette. By September 1992, McLellan retired and the following month, Dave Hill was the new Corvette Chief Engineer. The C5 Corvette would be Hill’s to design.– Scott
Bill Mitchell’s First Shark Corvette, the 1961 Mako Shark-I
Dateline: 8.7.19 – Photos from GM Archives –Upon Harley Earl’s retirement in 1958, William L. “Bill” Mitchell took over the reins as V.P. of General Motors Design. Earl hired Mitchell in 1935 and Bill essentially learned his trade working under Earl’s guidance. Mitchell was a car guy, an illustrator/designer, and came from the world of advertising. Bill was so good, such a natural, that a year after Earl hired him; he was put in charge of the Cadillac design studio! Mitchell got along famously with Earl, which was not an easy thing to do, as the 6”-4” Harley Earl was known to be a tough and intimidating taskmaster! By 1953, Earl handpicked Mitchell to be his successor, but warned Bill that he’d have to prove himself and make his own mark. Earl’s designs were long, low, and rounded. Mitchell’s philosophy was that a car’s lines should be crisp and sharp, like a freshly pressed business suit.
A year before Mitchell was given the keys to Earl’s Design Kingdom; he was tasked with designing a body for the proposed 1960 Corvette that was to be part of Ed Cole’s line of transaxle-equipped “Q-Chevrolet” cars. One of the members of Mitchell’s advanced design team was Peter Brock, the youngest designer ever hired by GM. One of Brock’s sketches was the closest to what Mitchell had in mind, and became the body for what was later called, the “Q-Corvette”. Unfortunately, the Q-Corvette never made it past a full-size clay mockup, as the entire Q-Chevrolet concept collapsed due to the high cost of tooling for the transaxles. But Mitchell couldn’t let go of Brock’s brilliant design. Shortly after Bill’s big promotion, he indulged himself by deciding to “go racing” with the 1957 Corvette SS mule chassis, draped in a roadster version of the Q-Corvette body design. This became Mitchell’s 1959 Stingray Racer.
Bill’s privateer racing effort wasn’t just “an executive at play”; he was testing the public’s reaction to what he had in mind for the next Corvette – HIS Corvette! Mitchell raced the Stingray Racer for two seasons and it was no secret at the track that the car was his. Even though the body of the car looked nothing like the then current Corvette, and didn’t say “Corvette” anywhere, a Fuel Injected 283 “Corvette” engine powered the car, and it was the VP of GM Styling’s car, so the connection was obvious.
Part of Mitchell’s natural genius was an inner knowing of what the public would like. The public response to the Stingray Racer’s body shape confirmed what Bill knew; the next Corvette would look like his Stingray Racer. Mitchell also understood “show biz” from his time in advertising and through working with Earl on many Motorama events. So, to keep stoking the Corvette and Chevy fans, he created a functional street version of the Stingray Racer. What looked like a prototype Corvette was in actuality another in a long line of teaser show cars. After nine seasons, Corvette lovers were ready for a new machine. The XP-755, aka, the “Mako Shark,” was truly the shape of the future. What Corvette fans didn’t know was that while the Mako Shark was knocking their socks off, Chevrolet was hard at work sorting out the final design of the 1963 Corvette.
This was no small task, as everything except for the engine, transmission, and brakes were completely new. Except for details such as, vent placement, grille, bumper shapes, and the shape of the coupe’s famous, iconic roof section, the second-generation Corvette was nailed down. Bill’s Mako Shark (the XP-755) was an exaggerated version of the work-in-progress 1963 Sting Ray (XP-720). The Mako Shark was a show car to tease the public, as well as Mitchell’s occasional personal daily driver. Think of cars, circa 1961, when looking at the Mako Shark! There were still cars from the late 1920s and 1930s on the road in 1961!
Larry Shinoda was Mitchell’s preferred, go-to stylist guy and seemed to be the best at pulling Bill’s ideas into reality. According to Peter Brock (National Corvette Museum 2017 Hall of Fame inductee), Mitchell was just as tough as Earl, but more jovial and at times profane. Bill just wanted to be “one of the guys”, but he knew what he wanted. (Brock’s book, “Corvette Sting Ray: Genesis of an American Icon” is a MUST READ for all second generation Corvette fans.) Since Larry Shinoda worked out the translation of Brock’s Q-Corvette design into the Stingray Racer, Larry was tasked to do the XP-755, “Mako Shark”. Larry was also working on the XP-720, the 1963 Sting Ray, in its development phase.
Keep in mind that show cars are supposed to be “over the top”. (Remember the 2009 “Transformers” Corvette Concept car?) Since Larry knew every line on the work-in-progress for the 1963 Corvette, he exaggerated and used older elements from the 1958 XP-800. Starting with a stock 1961 Corvette, the Mako Shark-I’s nose and tail had more “point” than the production Sting Ray would have, and was in fact, the nose was 12-inches longer.
Shinoda knew that Mitchell loved “surface details”, so the Mako Shark-I had lots to gawk at, including; gills in front of the front fender opening, recessed areas on the hood, grille details on the hood, tube header side pipes/mufflers, an XP-800-like bubble top with a periscope rear-view mirror system and grille-vents in the back of the bubble, scoops on the rear fender humps, vents behind the rear wheel well openings, and two pairs of triple taillights. The engine was a 327 with a small, Roots-type supercharger and four side-draft carburetors. Outrageous four-pipe side-pipes exited from each front fender. Originally the Mako Shark had a stock 1961 Corvette interior, except for tight bucket seats and a Ferrari steering wheel that was gift from Enzo Ferrari! Chromed Dayton knock-off wire wheels gave the car that “European look”.
Mitchell’s fertile mind was always expanding upon existing show cars and he had no reservation about pulling a show car back into his design studio for a refresh. Years later, the interior was redesigned with flat panels and gauges that looked very Ferrari-like, a 427 engine with an automatic transmission was installed, and Shinoda-designed alloy lace wheels shod with wide tires were used. The bigger wheel/tire combo nicely filled the wheelwell openings.
Unlike many of Harley Earl’s Motorama cars that were basically static, full-size model cars, Mitchell felt that his show cars should be fully functional vehicles, capable of being driven and shown off in public. As much as the completed 1963 Sting Ray is an iconic classic, I believe that if the Mako Shark-I, minus some of the show car pizzazz, had gone into production as the “1963 Corvette Sting Ray” it still would have been a success. Imagine the Mako Shark-I with the Sting Ray roof – that would have been hot! – Scott
Tommy Storino Builds a Bas-Ass Street Machine 1986 C4 Corvette on a Budget
Dateline: 8.5.19 – Photos by Tommy Storino and Jim Broschinsky – When the C4 Corvette made its debut in the middle of 1983, the press was agog. Even though the new C4 only had 205-horsepower (five more than in 1982) and 290-lb/ft of torque (five more than in 1982), the all-new structure of the C4 used all the power the 5.7-liter Cross-Fire Injection Corvette engine so much better than the previous platform. The difference between the C3 and the C4 was as stark as that of the C1 to the C2.
Several of the 1984 Corvettes the press got to play with were equipped with the optional Z51 Performance Handling Package for an extra $600. The Z51 package included; heavy-duty front and rear springs, sway bars, shocks, bushings, quicker steering, an engine oil cooler, and an extra radiator (pusher) fan. Chevrolet offered the Z51 package on Corvettes up to 2001, except for the years 1991 to 1995. That’s an impressive shopping list of suspension parts and it all worked great on the smooth test track the press was allowed to drive on.
But when Z51-equipped 1984 Corvettes hit the roads, customers were in store for a harsh surprise. On anything less than a smooth road, the car’s ride was extremely harsh; so much so that in 1985 both the stock and Z51 suspensions were softened up considerable. So, Corvette engineers over-did-it a little and had to dial it back.
The thirteen-year C4 story was one of continuous refinement. In 1985 and 1986 the Corvette was “The Fastest Car In America” topping 150-mph. In 1985 the two-injector Crossfire Injection setup was replaced with L98 Bosch Tuned Port Injection electronic fuel-injection system that bumped power to 230-horsepower. In 1986 the L98 engine got aluminum heads half way through the production year and power was up slightly to 235-horsepower. Power kept increasing steadily until the arrival of the 300-horsepower LT1 in 1992 and finally the LT4 engine in 1996 with 330-horsepower. The LT4 was rumored to be under-rated, with a more accurate rating of around 360-horsepower.
This non-stop improvement created an unusual situation. As the new Corvettes kept getting better and better, the earlier C4 Corvettes became less and less desirable. The “to-die-for” Corvette from just a few years before was becoming two-day-old bread, or like out of favor 45-records being placed in the back of the rack. Adding insult to injury, it seems that because early C4 Corvettes are at the bottom of the pecking order, many get abused and or ignored, and become basket cases.
However, this situation does create an interesting condition for Corvette enthusiasts looking for a donor car. Early C4 Corvettes can be had for as little as little as $4,000. But for Tommy Storino of Chicago, Illinois, his 1986 Corvette deal was bitter sweet.
Tommy’s Uncle Petewas a Lincoln Towncar man because he was a very big man; 6’-4” and 350-pounds. So the family was surprised when hebought a 1986 Corvette, and wondered if he was playing a joke on them. No one knew why he would ever buy a Corvette. Two months later, he died suddenly.
After the funeral proceedings were completed, Tommy’s cousin invited him to stop by the house to look at the mystery Corvette. Tommy’s cousin is a Jeep guy and wanted to restore the Corvette, but he just didn’t have the time. The car pretty much needed everything, except for the interior, which was in very good condition. But everything else; paint, tires, engine, transmission, you name it, was shot. And the car was leaking fluids.
When Tommy’s cousin handed him the keys, he thought his cousin wanted help getting the car out of the garage. Actually he did. Then his cousin said, “Take it, it’s all yours!” The car was drivable, but obviously needed a lot. Now Tommy had the beginnings of a project car, and he didn’t have to spend $4,000 for a donor car.
Storino’s project started in June 2015. Tommy explained, “I always liked the early C4 Corvette before they went with the round taillights and the LT1 engine. I liked the clean look of the early C4s and the digital dash. When I got the car it had a set of mint condition 1987 wheels and the paint was in terrible condition. I wanted something sinister-looking with racecar looks.” Black-on-Black-on Black was to be the overall theme.
The L98 Tuned Port Injection engine was pulled and completely rebuilt; nothing radical, but reliable. The all-black theme was carried over into the engine compartment with the only splash of color being the intake runners and valve covers hydro-dipped carbon fiber, Corvette badges on the valve covers, red ignition wires, and polished Exotic Muscle Longtube Headers.All of the car’s basic systems were refreshed; cooling system, brakes, power steering, shocks, and the automatic transmission was rebuilt.The rear suspension received new universal joints, the differential was refreshed, and a new 3.75:1 gear set was installed.
To achieve the racer-look Tommy was going for, the suspension was lowered one-inch. The ’87 wheels were swapped out for a full set of 1990 ZR-1 saw-blade wheels that Tommy had power-coated black and shod with ZR-1-size tires; P275/40ZR-17 on the front and P315/35ZR-17 on the rear.
Corvette racecars have ground effects, right? Tommy’s Corvette has a rear wing that he’s not sure of who the manufacturer is, but he’s been told that they are no longer being made and are quite valuable. The adjustable front splitter and rear defuser are both hand-fabricated.
Storino lucked out on the car’s black paint. The original paint was stripped and the body was in surprisingly good condition, with no major problems and no Bondo. Tommy requested GM Black paint, but his painter always wanted to paint a car with very expensive House of Colors paint, so that’s what he used and didn’t charge Tommy any extra for the paint. The GM Black has a small amount of brown in to warm up the black a little. The House of Color black has blue in it, giving it a cold-black look.
The taillights are custom-made LED units with black-tinted clear lens and the side markers are also tinted black. And the glass is tinted black. Tommy also installed HID headlights and HID fog lights. The only color on the car’s exterior is black. It all makes for a stark contrast when the windows are down with the factory Bright Red interior.
Appearance aside, one of the most interesting mechanical details on Storino’s Corvette is its exhaust. The Exotic Muscle Longtube Headersconnect to stainless steel 3-inch pipes with an x-pipes and MagnaFlow mufflers. Where the exhaust pips bend at the back to connect with the mufflers, Tommy had a solenoid-controlled cutout setup installed. “Cutouts” have been around for a very long time, but we typically see various kinds of Cat-Backs on Corvettes and not cutouts such as these. Tommy says, “Sometimes I just like to drive with open headers, just for fun!”
Between the Black-on-Black-on-Black with the Bright Red interior, the bodacious ground effects, bright LED lighting, and booming exhaust note, Tommy Storino’s 1986 former “basket case” Corvette is anything but subtle. After Tommy posted photos of his Corvette on social media, the car picked up the nickname, “Vader Vette”. We concur that the name totally fits. With the open headers you can almost hear Darth Vader saying, “Tommy… I’m… your Corvette!” – Scott
Dateline: 7.31.19 – As seen in the January 2019 issue of Vette magazine, Illustrations by K. Scott Teeters – When the 1963 Sting Ray made its public debut in September 1962, it was a total, “WOW!” And it wasn’t just the Corvette’s stunning new looks; it was the all-new chassis and suspension. By late 1959 Zora Arkus-Duntov was in charge of Corvette engineering. When Bill Mitchell’s design team started work on project XP-720 (the all-new Sting Ray), Duntov was called in to set the parameters for an all-new chassis. The completed Sting Ray looked like the sportscar from another planet and the chassis had everything except four-wheel disc brakes. Today the running chassis looks like a buggy compared to the stout aluminum, steel, and magnesium chassis’ of the C5, C6, and C7 Corvettes. But in 1963 the top-performing L84 Fuelie engine only had 360 “gross” horsepower and 352-LB/FT of torque putting power-to-the-ground with 6.70×15 bias-ply tires. That’s not much twisting on the chassis, so the chassis was more than adequate.
Even when the high-torque big-blocks arrived in 1965, for street use, the Duntov chassis could handle the job. The design didn’t start to show its limitations until the 1968 L88 racing Corvettes with wide tires started competing in long endurance races. Tony DeLorenzo once commented that after long 12 or 24-hour races, their Corvettes needed new frames. Their solution to this problem was a Logghe Brothers full welded-in roll cage. Greenwood’s wide-body Corvettes were so reinforced many asked, “Is there still a Corvette in there?” But for street use and spirited driving, the Duntov chassis served the Corvette well until 1982. Lets look at the chassis’ basics to see why it lasted so long
The genius of Duntov’s chassis was how much lower the center of gravity was. Chevrolet engineer Maurice Olley was a production car chassis and suspension expert when he designed the C1 chassis. As a racing expert, Duntov knew he had to get the center of gravity much lower. The C1’s chassis had a parameter frame with x-bracing in the center for rigidity. The car’s occupants sat on top of the frame. Everything measured from there; the cowl height, engine height, and everything else.
Duntov’s design eliminated the x-brace so that the occupants could be placed down inside the frame, dramatically lowering every data point from there. For rigidity the new frame had five crossmembers. Duntov then mounted the engine and transmission as low and as far back as possible and routed the exhaust pipes through holes in the second frame crossmember. The passenger compartment was pushed back as far as possible and the spare tire was mounted below the back of the frame and under the fuel tank.
The lowering of the engine/transmission and passenger compartment lowered the center-of-gravity from 19.8-inches to 16.5-inches. Moving major components as far back as possible in the shorter 98-inch wheelbase created a front/rear weight distribution of 47/53-percent. The engine centerline was offset 1-inch towards the passenger side because passenger footwell requirements were less than the driver’s. The extra offset reduced the transmission tunnel width and allowed the crankshaft and rear axle pinion to be on the same centerline. Ground clearance was just five-inches.
The build of the frame used boxed longitudinal sides with five crossmembers that were designed to suit the needs of styling. The new frame actually received computer analysis to determine the thickness needed for the parameters of the overall car. The front crossmember was welded to the sides and not bolted-on like the C1 chassis. The new frame with mounting brackets weighed 260-pounds, the same as the C1’s frame, but torsion rigidity increased from 1,587 lb/ft to 2,374 lb/ft per degree.
The C2/C3 suspension was a parts-bin marvel, although it didn’t seem that way. Duntov wanted an independent rear suspension and was immediately told, “No! It’s too expensive.” To get around this, Duntov used almost 60 full-size passenger car front suspension parts, including pressed-steel wishbones and ball-jointed spindles, and just rearranged them. The parts had already been engineered and proven, thus saving production cost. With a 9-degree slope, the wishbones gave an anti-dive reaction upon heavy braking. Then the inner pivot points were lowered to raise the roll-center to 3.25-inches above the ground. A recirculating-ball steering unit was placed behind the suspension and used a hydraulic damper to reduce kickback. All of these changes were very apparent when combined with the right shocks and anti-roll bars when the cars were first driven and tested. The money saved was more than what went into the rear suspension.
The independent rear suspension started with the differential pumpkin bolted to the 4th crossmember with the driveshaft as a device to control forward thrust from the wheels. Axle half-shafts with universal joints are on each side of the differential. Steel box-section control-arms carry the outer half-shafts and attach to the rear frame kickup assembly. Shims at the forward pivot-points are used to adjust toe-in alignment. Strut rods attach to the strut-rod bracket bolted below the differential and connect to the rear spindle support on the control-arms. The nine-leaf transverse spring with polyethylene liners between each leaf to reduce noise, mounts under the differential and is sprung against the rear portion of the control arm with long bolts. Duntov’s proposal to use a transverse leaf spring was not well received by Chevrolet chief engineer, Harry Barr, but no one could come up with a better plan.
For its time, Duntov’s chassis worked very well, but I’m sure that no one imagined it would be used for 20 years. The design proved to be easy to update. Disc brakes were in development when the Sting Ray came out and arrived on the 1965 model. When the new Mark IV became available in 1965 the suspension got stiffer front springs and larger diameter front and rear stabilizer bars. The new chassis was totally adaptable and could be made near-battle-ready with suspension component changes. During the 20-years of Duntov’s chassis, Racer Kits included; the 1963 Z06, 1967-1969 L88, 1970-1972 LT-1 small-block ZR1, and the 1971 big-block ZR-2. And from 1974-1982 there was the FE7 Gymkhana Suspension for spirited street driving. On the street, Duntov’s chassis could easily handle the 327 Fuelie to the LS6 454.
In the ‘70s chassis changes were made to conform to tightening regulations. Starting in 1973 the chassis had to handle the new 5-mph crash bumpers and steel side-door guard beams. In 1975 catalytic converters helped reduce emissions, but cloaked engines. A steel underbelly had to added to the chassis as a heat shield against the very hot converters. 1980 saw a big weight reduction from 3,503-pounds to 3,336-pounds thanks to an aluminum differential, lighter roof panels, thinner material on the hood and doors, and the use of the aluminum L84 intake manifold on the standard engine. The following year, a fiberglass-composite rear leaf spring helped shed 29-pounds. Early ‘80s Corvettes don’t get much respect because their restricted engines, but their drivetrain and suspension was as good as ever. An early ‘80s Corvette with a classic SBC crate engine would make for a stout performer.
Yes, Duntov’s chassis looks crude by today’s standards. But Corvette development is always empirical. If it weren’t for the C2/C3 chassis, there never would have been a C4 chassis, and so it goes. – Scott
The long and winding road to the mid-engine C8 Corvette
Dateline 7.18.19 –The waiting is finally over! The “pie-in-the-sky” dream of Zora Arkus-Duntov of a mid-engine high-performance sports car wearing a Corvette badge has arrived. The journey to the mid-engine C8 was long, very long.
The C7 Corvette debuted on January 13, 2013 and by the end of April 2013, Chevrolet announced pricing and hard details. By the third quarter of 2013 C7 deliveries began. Then on August 14, 2014, less than a year after C7 production began, Motor Trend announced online, “SCOOP! Mid-Engine Chevrolet Corvette is a Go”.
I said, “HUH?!?!? The C7 just came out. Come on, quit it with the mid-engine tease!
That was almost five years ago and Corvette fans were tortured mercilessly with rumors, spy images, and 3D renderings. It seemed like “The Never-ending C8 Mid-Engine Corvette Story”. Oh, sure! And now, here we are. The journey to the C8 mid-engine Corvette has become epic.
Duntov passed on in 1996, so we can’t ask him exactly when did he first want a mid-engine Corvette. Duntov knew all about mid-engine sports racing cars dating back to the late 1930s. He built the mid-engine CERV-I in 1959/1960 and the mid-engine, all-wheel-drive CERV-II in 1963/1964.
There were numerous mid-engine cars built at the GM Tech Center in the 1960s that were not specifically Duntov’s cars. The first running, “Duntov” mid-engine vehicle that wore the classic Corvette cross-flags was the 1970 XP-882. This car seriously looked like a Corvette. The 1968 Astro-II looked like a Corvette, but that was R&D chief engineer Frank Winchell’s car. But Duntov got to carry the mid-engine torch.
When Duntov retired and handed over the reins to new chief Corvette engineer Dave McLellan, he told the new chief, “Dave, you must do mid-engine.” Although Duntov was a corporate anomaly during his 21-1/2 years at Chevrolet and many didn’t miss him, he definitely had the hearts of legions of Corvette fans and many GM and Chevrolet insiders.
In 1992 Corvette engineers and managers put three unique proposals on the table for consideration for the C5 Corvette. The three concepts included; the mid-engine CERV-III, a stiffer, lighter, restyled version of the C4, and the “Momentum Architecture”. The CERV-III was too expensive and no one wanted the “stiffer-lighter” concept. The Momentum Architecture design won the contest and became the C5. The C6 and C7 designes are advanced, improved designs of the basic C5 structure.
Jim Perkins was the general manager of Chevrolet in the early ’90s and out of respect for Duntov, he invited the great man to see Dave Hill’s presentation to GM leaders to review past, current, and potential future Corvette designs. Zora didn’t say much.
According to the Motor Trend post on May 4, 2014 titled, “How the C5 Chevrolet Corvette Was Saved”, Perkins had the following exchanges with Duntov a few days later.
“Two or three days later, he called and said [imitating Duntov’s Eastern European accent], “Jim, I look at new Corvette architecture, and I am surprised. No mid-engine.” I said, “No, no mid-engine.” He asked, “Why? Why you make decision no mid-engine? You should fight for mid-engine.”
I said, “Zora, I might as well be fighting the wind. I’m not going to win that one. We’ve got the program, we’re going to go forward with it, we have a great architecture that we’re pretty well settled on.” He said, “No, Jim, you must raise issue of mid-engine.”I said, “OK, fine.”
He said, “I would like to come see you.” I said, “Well, I’m pretty busy, but my secretary will try to find a time.” I thought he was going to come in just to talk, but when he walked in that morning, he had a role of stuff under his arm. He said, “I am here to talk about mid-engine car.” I said. “OK, but I don’t know what there is to talk about.”
He rolled out these plans that he had done himself, and started talking about this mid-engine architecture. I said, “Zora, I’d like to sit here and talk with you about this, but I’m very busy, I have other things I need to do. Nothing has changed. We are not going to do a mid-engine.”
He said, “You are not going to fight for mid-engine?” I said, “No, sir. I am not. It’s a waste of time and effort. There is just no point in trying to do it. I know you’re passionate about it, and you’re probably right, but we just cannot do it.”He said, “OK.” And he rolled up his plans, put them under his arm and said, “You are not going to build mid-engine. I will raise the money, and I will build the son-of-a-bitch myself.”And he walked out of the office.”
After decades of jaw, jaw, jaw about a factory production mid-engine Corvette, it is finally here. Some time this summer the last front-engine Corvette will roll off the Bowling Green assembly line, closing the long chapter on front-engine Corvettes. Wherever Duntov’s spirit is in The Multiverse or out there in the Either, we all hope that he is happy that his production mid-engine Corvette is finally a reality. – Scott
The Corvette Chassis That Maurice Olley & Mauri Rose Built
Photo: GM Archives
Dateline 7.17.19, As seen in the December 2018 issue of Vette Magazine – Corvettes are kind of like a beautiful woman. Sure, she’s a beauty, but is she smart and athletic? From the beginning, Corvettes have consistently been unique, beautiful cars that look like nothing else on the road. Even the hardboiled engineer and racer Zora Arkus-Duntov was disarmed by the beauty of the 1953 Motorama Corvette, such that he immediately knew he wanted to be part of Chevrolet’s bold American sports car effort. (Zora was always a pushover for beautiful women!)
Graphics: K. Scott Teeters
Now, it is no secret that the 1953 Corvette cars were more like “pilot program cars” or “work in progress cars.” The assembly workers and designers were literally grooming and refining Corvettes as they were being built for sale! Consequently, many of the early Corvettes from 1953 to 1955 weren’t so good.
Graphics: K. Scott Teeters
While the initial response by the press was very positive, as cars were road tested and customers gave their feedback, the Corvette’s glow diminished. The term “parts bin car” started being bantered about. This is only partially correct and dishonors the fact that the first Corvette’s chassis was designed by one of the best chassis men of the day, Maurice Olley. Former Allison Engineering Company engineer and three-time Indy 500 winner, Mauri Rose, oversaw construction of the first Corvette chassis.
Graphics: K. Scott Teeters
The original mission of the Corvette was to be a “sporty” street Chevy, not a racecar. The basic design and structure was so good for its day that after the bugs were worked out, and Zora Arkus-Duntov and Mauri Rose started developing racing parts for Corvette customers, a properly optioned Corvette could easily be made into a competitive SCCA racecar! In fact, with the basic design in tact and optioned with the Fuelie engine, racing suspension and brakes, Corvettes were dominating SCCA B/Production and A/Production classes by the late 1950s and early 1960s.
Photo: K. Scott Teeters
Three hundred Corvettes rolled off the makeshift assembly plant in Flint, Michigan between June 30, 1953 and December 24, 1953. When the St. Louis plant came online on December 28, 1953, Chevrolet produced 3,640 Blue Flame Six-powered, 1954 Corvettes – now available in four colors: Polo White, Pennant Blue, Sportsman Red, and Black. 1955 saw the introduction of the all-new, lightweight 265 Chevy engine and a 3-speed manual transmission – you’d think that sales would have seriously taken off – but they did not! Only 700 1955 Corvettes were built and only seven had the Blue Flame Six engine. What happened?
Photo: K. Scott Teeters
Obviously, the car stumbled off the starting line. Corvettes were expensive and the build quality was spotty at best. Even the heater and radio were optional! Keep in mind that from 1953 to 1954, there were no mainstream-manufactured American sports cars. (Ford’s Thunderbird arrived in 1955.) Sports cars were a very, very small automotive market segment. From 1953 to 1955 Chevrolet sold 4,640 Corvettes compared to 1,774,238 Bel Air cars! European sports cars were being imported to America in the early 1950s, but in very small numbers compared to the gigantic market for big American cars.
Outside of the very small world of sports car enthusiasts, the Corvette made no sense at all. The Thunderbird “made sense” because it was loaded with creature comforts and had a solid, steel body with real roll-up side windows. That’s why even though the prices of the two cars were very close, Ford sold 16,155 Thunderbirds in 1955, compared to 700 ’55 Corvettes. T-Bird sales dipped to 15,631 in 1956 and then hit 21,380 in 1957, just in time for Ford to abandon the 2-seater sports car market in favor of the four-seater personal luxury car segment.
Photo: K. Scott Teeters
The two biggest criticisms of the Corvette were the six-cylinder engine and automatic transmission. Lets take this apart. In-line six-cylinder or four-cylinder engines powered most European sports cars of the day, and several had exotic, double overhead-cam heads. Automatic transmissions were considered state-of-the art, advanced American automotive technology in the 1950s. Automatics freed drivers from dealing with clunky gearboxes, loose shifters, stiff clutches, and double-clutching. The automatic transmission was seen as a luxury feature.
Graphics: K. Scott Teeters
Motor Trend Magazine’s editor (and MG owner), Walt Woron had this to say about the ’53 Corvette, “To a purist like me the idea of an automatic transmission in a sports car is unthinkable, even if the lever is next to the drive shaft tunnel.” But after three-time Indy 500 winner Mauri Rose gave Mr. Woron a ride around the GM test track, easily downshifting, braking, and accelerating out of corners, Woron said, “I had to admit grudgingly that an automatic could be at home in a sports car.” It is ironic that today the C7 automatic Corvette delivers performance on par with the manual transmission C7. It seems that we have come full-circle.
But the unkindest insult leveled against the C1 Corvette was that it was a clumsy attempt by Chevrolet to build a “parts bin sports car.” As if to say that Harley Earl, Ed Cole, Maurice Olley, and Mauri Rose slap-dashed together car and presented it as “America’s sports car.” I will dispel this myth once and for all. Although it was Harley Earl that came up with the concept and directed the shape of the first Corvette, it was Chevrolet’s new chief of engineering and soon to become general manager, Ed Cole that was the corporate driving force behind the project. Cole was part of the generation of WW-II era men with a “Let’s get it done, now!” attitude. Cole loved being a corporate rebel. His motto was, “Kick the hell out of the status quo!” Cole liked to “shake things up” so he created his Dream Team to create his Chevrolet sports car.
Photo: Amazon.com
Maurice Olley was in the closing years of his long career as an engineer and was recognized as one of the best suspension and R&D engineers of his time. Olley was British had been the personal designer for Sir Henry Royce (as in, “Rolls Royce”) and was later the chief engineer for Rolls Royce in America. From 1930 to 1937 Olley was a special projects engineer for Cadillac and General Motors. During WW II Olley was the engineering representative for Rolls Royce LTD, USA (aircraft engines) and then was appointed to the British Ministry of Supply (tanks). Cole hired Olley in 1952 and knew he had the best chassis engineer he could find. Olley had over 40 U.S. and Canadian Patients to his name, authored numerous technical papers, and wrote the book, “Chassis Design: Principles and Analysis”. (This book is available on Amazon.com)
Photo: AutoWeek.com
Mauri Rose was an engineer first and a racecar driver second – but his driving was a mighty fine “second”! Rose was the third driver to win the Indy 500 three times – 1941, 1947 and 1948. The first was Louis Meyer 1928, 1933, and 1936. The second was Wilber Shaw in 1937, 1939, and 1940. Rose was also one of the test drivers for GM’s 1953 Firebird XP-21 gas-turbine experimental car. Mauri drove the experimental car at (where else?) the Indianapolis Speedway – just for “feasibility testing.” Fourteen years later in 1967, Parnelli Jones almost won the Indy 500 with the STP-Paxton Turbine-Engine racecar.
Photo: GM Archives
When Ed Cole hired Rose, he told him, “You’re the man to do the sports car!” The rest of the main players on the dream team roster included stylist Robert McLean and body engineer Ellis “Jim” Premo. McLean was tasked with establishing the basic parameters for Earl’s Project Opel sports car. He set the wheelbase at 102-inches and placed the in-line-six engine back seven-inches closer to the dash than in a regular Chevy. Weight distribution came in at 53/47 front-to-rear. Earl wanted trendy wrap-around windshield glass and clear plexi headlight covers.
In April 1952, using a full-size model, Ed Cole and Thomas Keating pitched the concept of an “American sports car” to GM president Harlow Curtice. They were seeking approval to build an experimental version to showcase at the 1953 Motorama show. Curtice liked what he saw and approved the project. With an approval in hand, Cole showed Maurice Olley the full-size model and tasked him with designing a suitable chassis. The task was to: “produce a sports car, using existing, reliable components, adequate performance, comfortable ride, stable handling, in less than seven months to the Motorama Show and 12 months to production.” Ten days later, Olley had the basic chassis design sketched out for “Project Opel.” The name “Corvette” would arrive in September 1952, thanks to the work of Chevrolet PR man, Myron Scott.
Photo: K. Scott Teeters
Here are the basics of Olley’s “Project Opel” chassis. The box side rails were made from two U-channels per side, nested together in opposite directions to form a box-section, then stitched-welded together, and shaped. The center X-member was made from I-beam steel with holes cut in the “I” part of the beam for the duel exhaust to pass through. There were 11 body mount points on the chassis. The completed frame weighed 213-pounds – considered “light” in 1952!
R&D engineer, Walter “Walt” Zetye worked out the final details of the suspension and steering systems. The independent front suspension, while looking quite ordinary, had just been totally redesigned in 1949 by GM engineer Kai Hansen. Maurice Olley had also done independent front suspension R&D work for GM in the 1930s while running the Product Study Department. For its day this was considered a major improvement over I-beam front axles. The one-inch diameter Delco shocks were mounted inside each coil spring, between parallel-wishbone A-arms, with kingpin spindles and ball joints. The oversized front sway bar was mounted high atop the front engine cradle/crossmember that was bolted to the right and left side rails.
Photo: K. Scott Teeters
The rear suspension used a stock Chevy differential with 3.55:1 gears and 51-inch long Chevy leaf springs, commonly known then as a “Hotchkiss drive system.” The Hotchkiss system used a driveshaft with universal joints at both ends. Most Detroit cars used a torque tube that only had one U-joint behind the transmission. Because the centerline of the crankshaft/transmission driveline was above the X-member of the frame, U-joints were needed at both ends of the 36-inch driveshaft because the rear axle input was lower than the engine/transmission centerline. The rear axle sat atop four leaf springs and was held in place with U-bolts. The leaf spring shackles held the rear axle in position for-and-aft. Rebound straps limited rear axle rebound. (In 1959 radius rods connected both sides of the rear axle to the frame rails to cure wheel-hop.) A Saginaw worm-and-sector steering box was used with a mildly-quick 16:1 steering ratio. Remember, this was the days of no power steering, so steering ratios were high and steering wheel diameters were large for increased mechanical leverage to make steering easy. Brakes were to be the bane of Corvette racers for years, but for street use, stock Chevy brakes with 11-inch drums were used on all four wheels and were considered adequate.
The Blue Flame Six engine is much maligned, but for its day, was pretty stout and had many improvements over the old 235-CID, 115-hp Stovebolt Six. Inside, the Blue Flame Six had aluminum pistons (a first for this engine), improved lubrication, and more durable main bearings. Compression was bumped up to 8:1 and a more aggressive solid-lifter cam was used with .405-inch intake lift and .414 exhaust lift. A metal cam gear replaced the standard fiber cam gear, dual valve springs and stronger exhaust completed the valvetrain. A high-efficiency water pump was installed and shielding was added to the distributor and plug wires. To eliminate the need for a hood bulge, three horizontal Carter one-barrel carbs were used and mounted to a special aluminum intake manifold. The exhaust system used a split manifold with dual exhaust pipes and mufflers. A high-efficiency water pump with a remote header tank for the radiator kept the hot-rodded Blue Flame Six in the cool zone. While the final version of the Blue Flame Six was rated at 150-horsepower, Mauri Rose said, “We finally got 190-horsepower… but the idle isn’t so good and it didn’t start so well… so we gave up on the roller-camshaft. We ended up with around 150-160-horsepower.”
Photo: GM Archives
Mauri Rose literally hand-fabricated the very first Corvette chassis as if he was constructing a purpose-built racecar. Rose later said, “We did all the work in a loft, not the Chevrolet factory. We built the whole chassis there. This was a crash program. They took their sketches right to the build shop and roughed up the chassis in wood and Styrofoam right off the drawing boards. If it wasn’t right, they tore it down and started over.”
The use of the 2-speed Powerglide automatic transmission was purely for expediency. It was the least costly way to build the car on such a short notice. The three-speed manual transmission arrived in late 1955 and the four-speed in 1957. Most Americans considered the automatic transmission an automotive advancement, but to traditional sports car buffs, this was sacrilege. Performance of the 1953 Corvette was considered “good” for its day: 0-60 time was 11.5-seconds, the quarter-mile in 18-seconds, and the top speed was 110-mph.
Here’s how Maurice Olley defended the Corvette’s automatic transmission,“As the sports car appeals to a wider and wider section of the public, the center of gravity is shifting from the austerity of the pioneer towards the luxury of modern ideas. There’s no reason to apologize for the performance of this car with its automatic transmission.” Clearly, Olley wasn’t into racing, but then again, in 1952 when the Corvette chassis was being designed, here was Chevrolet’s official statement for their new two-seater sports car; “The car is not intended to be used as a racing car.”(By 1956 this was not the case.)
Illustration: K. Scott Teeters
While the first three years of the Corvette were rough, the basic structure design was unchanged from 1953 to 1962. The makeover of the 1956 model was a game-changer, even though the basic structure and interior were the same. The public was used to seeing new designs on familiar cars, so a refresh wasn’t that unusual. The new design was still looked clean and light. Because Duntov went on to become the Corvette chief engineer, Zora is generally credited with the long series of performance parts, unofficially known as “racer kits.” However, there’s more to that story.
Rose and Duntov’s experience and expertise was so valued that in September 1955 Ed Cole decided that starting with the 1956 Corvette, the two men would be responsible for the design and development of RPO equipment necessary to make the Corvette capable of competing in racing events. By January 1956, “racer kit” options started to become available. This was the beginning of Chevrolet’s first venture into the world of factory-backed sports car racing, as plans were laid out for a racing team to field modified Corvettes to race at Sebring and Le Mans.
Illustration: K. Scott Teeters
Initially, Duntov was not excited about the plan because of the1955 Le Mans disaster that killed 83 spectators, one driver, and injured over 120 others just a few months before. Zora knew the Corvette’s brakes weren’t up to racing standards and did not want to see a Corvette cause a similar disaster at Sebring. This was no doubt the impetus for the elaborate brakes that were part of the 1957 RPO 684 Heavy Duty Racing Suspension option.
Photo: K. Scott Teeters
Early in 1956, Chevrolet’s Marketing Department encouraged Corvette customers to race their Vettes with an ad headline that read, “Bring on the hay bales!” After the Corvette’s big class-win at Sebring in the March 1956, Chevrolet ran an ad featuring the Corvette Sebring racer with the headline, “The Real McCoy”. Chevy’s new general manager, Ed Cole announced, “We’re in the sports car business to stay.”
Photo: GM Archives
The magic that Duntov and Rose delivered via their RPO program was pure, racing parts development. Duntov and his engineers improved shocks, shock mount points, springs, sway-bars, brakes, rear suspension, added rear trailing arms, and many other small details. This added up to a car that was a solid foundation for a serious SCCA B/Production and A/Production racecar. Rose got the prototype parts to the racers and even thrashed a few Corvette racecars with Smokey Yunick. Rose’s strong, “Let’s get to work and get dirty!” work ethic impressed Yunick, a man NOT easily impressed! Smokey said about Rose, “He was a hard-working, sharp, ‘run to win or bust’ sort of cat.”
Photo: Amazon.com
Maurice Olley retired on December 31, 1955 and was inducted into the National Corvette Museum Hall of Fame in 2008. Mauri Rose went on to drive the 1967 Camaro Pace Car at the 1967 Indy 500 race, after which he faded into automotive history, and died on January 1, 1981 at the age of 74.
Photos: GM Archives, Graphics, K. Scott Teeters
So, when you see stories about championship C1 Corvette racecars, remember that the commonality they all share is that they ride on the chassis that Olley and Rose built. – Scott
Dateline: 7.15.19 – As seen in the January 2018 issue of Vette Vues (All images GM Archives) – A new era began on December 1, 1958 when William L. “Bill” Mitchell took over the reins of GM Styling from the great Harley Earl. Mitchell started his career as a young illustrator that loved rendering cars, racing cars, and hanging out with the Collier Brothers, the creators of the Sports Car Club of America (SCCA). It was Harley Earl that hired 23-year old Mitchell. From there, Bill learned the business end of the automobile business by working directly for Harley Earl and was in fact, Earl’s handpicked successor.
But when Mitchell took over, it was a whole new game. Harley Earl loved rounded shapes and lots of chrome. Bill Mitchell loved slim shapes, with fine, crisp lines. Bill believed that the lines of a car should be “crisp”, like a freshly pressed suit. That’s an important concept to hold on to as we look at the Corvette show cars of Bill Mitchell.
Mitchell’s first indulgence as GM’s Styling V.P. was the acquisition of the 1957 Corvette SS “mule” chassis for a nominal amount (I’ve read anywhere from $1.00 to $100), to use as the foundation of his own racing ambitions. Bill had Larry Shinoda work Peter Brock’s basic Q-Corvette shape into the 1959 Stingray Racer. While Bill was busy racing his Stingray Racer, there often was an accompanying custom Corvette that got a lot of attention.
Mitchell had initiated a policy that all dream cars and show cars would be fully functional. No mockups or static shells. Since Bill liked to drive his designs, they should also have plenty of power under the hood. Mitchell liked his cars “loaded for bear!” This was a trend that all Mitchell show cars had. The XP-700 also showed styling elements that would be used on the 1961 to 1964 Corvettes and believe it or not – the 1997 Corvette!
The XP-700 was built on a 1958 283 Fuelie Corvette. In 1950s excess style, everything is “bigger and better”. The front was pure “custom car design” with an elongated, elliptical nose and a scoop under it. Mitchell wanted to break away from the Earl driven, big toothy grille, towards something slim and lightweight. The now-classic Dayton Knock-Off Wire Wheels were part of the effort to make the car look lighter. The Lucas spotlight headlights are moved forward and also had scoops under them. The recessed hood vents showed up on the 1963 Corvette, but with fake grille inserts, and the 1964 Corvette, sans the grilles. The front fender scoops were shorter versions of the production 1956-1957 fender scoops.
Show cars have to have plenty of flash and sparkle. The 283 Fuel Injected engine was festooned with lots of chrome and black crackle-finished parts. Today, these kinds of parts are easily available through aftermarket Corvette parts companies, but in 1959, this kind of finish was spectacular. Mitchell loved loud side-pipes; consequently most of his Corvette show-cars had them. Looking more like a custom car setup, the side pipes are interesting, but were a little too short, looking like add-ons, as do the scoops behind the doors.
The transparent, bubble top idea was a hold over from the “Jet Age” years of auto styling. To help reduce solar heat, panels of vacuum-deposited aluminum film was placed on the inside of the double-bubble, over the driver and passenger. Between the two bubbles was a metal strip with a periscope rear-view mirror on the top and towards the back cooling vents. The entire top looked like a prop from a 1950s Sci-Fi space movie or something from The Jetson’s animated TV cartoon series. A “transparent roof” option wouldn’t be available until 1978, after years of experimentation with UV Light-blocking transparent films. A toned down version of the twin bubble top roof shape finally arrived in 1997 with the all-new C5.
There were two versions of the tail section. The original version was very short. Then in October 1959 the tail was lengthened, looking more like the production 1961-1962 Corvette. A body crease leads off the tops of the wheel openings and wraps around the back. Below the back edge, the license plate was mounted deep in the center. Now Corvette classic “dual round taillights” flank both sides of the license plate and vertical bumpers were at the corners. The basic shape, with horizontal bumpers, was put into production for 1961 and 1962, and set the design for the back end of the 1963-1967 Sting Ray convertibles.
The interior had features that became standard in 1961, such as the parking-light warning light, dual sun visors, windshield washers, and interior courtesy lights. Yes, early Corvettes had spartan interior amenities. Features that didn’t go into production were the stainless steel foot well grates, the periscope rear view mirror (a primitive version of modern rear-view video monitors), an experimental overdrive unit (tall highway cruising gears are now built into basic transmissions, typically as 5th or 6th gear), and a dash-mounted chronometer (a basic feature that’s now part of the Corvette’s GPS and Performance Data Video Recorder information system). Many of the “gee wiz!” special features of factory show cars from long ago are now either standard production features or special options.
The XP-700 was the first of the street-worthy Corvette show cars. Silver and red were Mitchell’s favorite colors to use on most of the show car Corvettes. The XP-700 wore both colors in its early years. Unlike today’s show cars, Mitchell actually drove many of his show cars to and from work – even the Stingray Racer! From the days of Alfred P. Slone, GM has always had a tight corporate structure, and when Bill Mitchell was rising through the ranks, everything at the corporate level was blue and gray suits. Mitchell was definitely a corporate “Rebel With An Attitude” and was well known for his bright-colored, flamboyant suits.
As Chuck “The Chrome Cobra” Jordan (Chief of Styling from 1986-to1992) used to say concerning Mitchell, “The man had flare!” Thanks to Mitchell’s “flare” from 1959 to his retirement in 1977, Corvette fans were treated to a steady flow of exciting Corvette show cars. – Scott
Dan & Sue Black’s “Georgia Special” 2015 Z06 Corvette
Dateline: 7.8.19 As seen in the October 2018 issue of Vette Vues Magazine –We all come to the Corvette world in our own unique ways. For some of us, it’s a childhood thing that goes back so long that we almost can’t remember not loving Corvettes. And for others, they’ve always been a car guy, and Corvettes came to them later in life.
Dan Black has been a self-described “car fanatic” all his life and over the years has had lots and lots of cars, mostly old “classic” cars. He even learned to drive in a 1928 Ford Model A! The delightful thing about the old classics is that if you are mechanically inclined, you can pretty much figure out how they come apart and how to repair and restore them. Dan learned the in’s and out’s of cars through a lot of trial-and-error, sweat, and skinned knuckles.
Along the way, Dan became a fan of the Chevy 3100 (1/2-ton) trucks produced from 1947 to 1955 and even restored four of the classic Chevy trucks. Dan also owned a ’23 T-Bucket hot rod, and a ’40 Buick Coupe. In 2008 after Dan sold his last 3100 Chevy truck, he decided to do a Corvette. His children were pretty much all grown up and it seemed like it was time for a Vette.
Dan found a 1985 Corvette to make into a project car. Early C4s and cheap and plentiful and you can seriously personalize them without ruffling feathers in the Corvette community. The tired old L98 Tuned Port Injection engine was replaced with a 383 stroker Chevy crate engine and the car was painted Corvette Velocity Yellow. Dan’s restoration skills paid off on the Corvette, as his car won the World of Wheels Show in 2012.
But it was an August drive from Georgia to the Corvettes at Carlisle Show in 2014 that was a game changer. Dan explains, “The car was nice, but the nearly 1,400 mile round trip in our 25 year old Corvette really beat us up. The car rides really rough, so we knew we had to get something newer and the prices of the C5 were just right.” So Dan and his wife Sue bought a 2002 Z06 Corvette that was comfortable, really quick, and fun to drive.
Dan and Sue were already into the Corvette lifestyle and were members of the Corvette Cruisers of AtlantaCorvette Club. In 2014 when the C7s came out, Dan saw club members rushing to Chevy dealers to place orders. Of course, two minutes after the C7 made it’s debut in January 2013, the first question was, “So where’s the Z06?” Since Dan Sue were C5 Z06 owners, they decided to wait.
In February 2017 Dan and Sue bought what we have to call, their “first” 2015 C7 Z06. We use the word, “first” because in October 2017 the car was totaled! A rear end collision caused severe damage to the frame, to the tune of $70,000 worth of damage! Needless to say, the insurance company totaled the Z06 Corvette. We hate to see any Corvette totaled, but it happens. Dan immediately started searching for a replacement Z06 and found the perfect car in Orlando, Florida, but this one was better.
The seller in Orlando was actually the second owner of the the loaded 2015 Velocity Yellow Z06/Z07 Corvette. The original owner was a pain management doctor from California that ordered the car from F.C. Kerbeck in Atlantic City, New Jersey in March 2015. Money was no object, so the doctor ordered nearly every option available, including the Z07 Performance Package. The doctor only owned the car for eight months, but before he sold the car to a man in Orlando, Florida, he had a custom-built roll bar, painted Velocity Yellow installed in the car. Aside from the roll bar, everything else is factory.
When the C7 Z06 made its debut heads spun at the news of the LT4’s 650-horsepower and 650 lb/ft of torque rating. That was a 145-horsepower jump from C6’s 505-horsepower LS7 engine, and twelve more horsepower than the C6 ZR1’s supercharged LS9 engine. That was way more than Z06 fans were expecting from the C7 Z06. But it’s amazing how quickly we can get used to more power. So, what’s an owner of a 650-horsepower C7 Z06 wanting “more” to do? Go get more power!
The awesome thing about GM’s latest LS series performance engines is that extracting more horsepower is not that difficult. The Orlando owner chose to take his Velocity Yellow 2015 Z06 to Redline Motorsports in Pompano Beach, Florida for a Phase 2-C7Z performance package. This performance package includes the following; 1-7/8” Long Tube Stainless Steel Headers, High-Flow cats and 3” Mid-Section with X-pipe; ATI-redline Lower Crank Balancer Assembly;15-percent Overdrive Crank Pulley; HD Drive Belt; Halltech Stinger High Capacity Cold-Air Intake; Brisk Spark Plugs; and Custom E92 Calibration. This package takes the 650-hp / 650 lf/ft torque LT4 engine up to 730-hp / 737 lb/ft of torque.
People sell awesome cars for all kinds of reasons. For whatever the reason was, the Orlando owner decided to put his car up for sale, just at the same time Dan and Sue were looking for a replacement for their totaled Z06. The price was right, the options couldn’t have been any better, and the color was perfect. Dan and Sue Black were back in a Velocity Yellow Z06, with the Z07 package, to boot!
After buying the car, the first thing Dan wanted to address was the car’s paint finish. Yes, the Velocity Yellow’s paint “finish”. Chevrolet has come a long way from the olden days in St. Louis when all Corvettes were sprayed with lacquer in less than optimal conditions. And you have probably heard the news of the Bowling Green Corvette Assembly Plant’s new $439 Million dollar Paint Shop. Even in 2015, some colors used on Corvettes showed slight orange peal more than others. White is the most forgiving, but the more vibrant colors not so forgiving.
Because this can be remedied, Dan had the paint corrected. The process removes a small amount of the clear coat by using mild abrasive polishes worked into the surface with polishing machines. The finished process levels out the surface, thus removing the slight orange peal. Then, 65-percent of the car was covered with Expel Clear Bra material.
The rest of the car was expertly treated with three coats of Gyeon Ceramic Coating by Al Batthurst of Shiny Fenders, in Grayson, Georgia. This advanced coating is available for painted body surfaces, glass windows, wheels, interiors, calipers, tires, and trim. Dan reports that thanks to the Gyeon coatings, clean up and prep time for showing his Z06 is dramatically reduced.
Another special touch that Dan and Sue added to their Z06/Z07 is the custom airbrushed under hood liner by artist Steve Ray, from Bowling Green, Kentucky. Ray’s rendition of an American Bald Eagle bursting through the hood and the C7 Corvette logo is spectacular, and a crowd favorite when Dan and Sue show their car. And lastly, since the car is equipped with the Z06 and Z07 aero packages, Dan added an Anderson Composites rear diffuser. There is so much race car built into the Z06, and since the C7.R Corvettes have rear diffusers, why not put one on the car.
Dan and Sue Black’s 2015 Velocity Yellow Corvette is essentially completed, but we all know that cars such as this are never truly “finished”. At the Festivals of Speed Car Show event in Alpharetta, Georgia, just north of Atlanta, the car won Best Contemporary Corvette. Every show Dan has taken the car to he has won 1st place.
Here’s what Dan has to say about owning and living with his 730-horsepower Z06, “The car is very comfortable and there’s no comparison to the C4 we owned. We loved the C5 Z06, we really did, but the C7 is totally different. The responsiveness of the car is just amazing. I also have a 1968 SS Camaro with a 540-cubic-inch all-aluminum Merlin big-block with 700-horsepower. But the Z06 Corvette is such a pleasure to drive. So far, according to the car’s computer, the lifetime average fuel mileage is 24.7-mpg. We recently took a 150-mile trip from Atlanta to Birmingham, Alabama, and with the cruise control on and driving at the posted speed limits, the Z06 recorded 36-mpg. I’m satisfied with that.”
We asked Dan about future plans for his Z06 /Z07 Corvette. He answered, “Enjoy the car and let others enjoy the car at car shows.” Sounds good to me. Save the Wave, Dan! – Scott
Dateline: 2-28-19 – Images: GM Archives; Graphics & by K. Scott Teeters
Of the six men in our “Corvette’s Founding Fathers” series, Peter Brock had the shortest career at GM, but his contribution was enormous. Like all of the Founding Fathers, Brock had “gasoline in his veins” and was cut from the same cloth as Larry Shinoda; post-WW-II southern California, the birthplace of modern hot rodding.
Brock got the car bug at the age of 12 when he spotted a 1949 MG TC with a broken engine in back of the garage where he had his first after-school job. Brock studied the lines and mechanicals of the MG TD and at 15 bought the car. With help from his car pals, he got the car running. Brock’s second car was a 1946 Ford that he made into a fast, award-winning hot rod. Whereas Shinoda’s “Chopsticks Special” hot rods were scrappy-looking drag racers, Brock’s Hot Rod Ford was a sleek beauty that was quick at the drags and had class-wins at the Oakland Roadster Show in 1954 and 1956
.While pit crewing for some older car pals that were racing, Brock decided that he wanted to race, but Brock observed that racing was an expensive enterprise. He determined that he’d better first learn a trade. And since automotive design was his second passion, he’d have to go to Art Center College of Design.
Brock’s approach to getting into the school was stunning; he walked in and told the receptionist that he wanted to attend. The lady asked about his portfolio and Brock had to admit he didn’t know what a portfolio was. After she explained, Brock went to his car, created a series of drawings on blue-lined school paper, came back in after a few hours and said, “Here’s my portfolio.” He made his case that after a month, if his work wasn’t approved, he’d leave.
Brock didn’t see much value in life drawing, light and shadow, and graphics classes. But the “Transportation 101” class was exactly what he was looking for. With great teachers, classmates, and his enthusiasm, Brock was ready for his next big break. His only problem was that he ran out of money! GM Designer Chuck Jordan was then working as a headhunter scouting new talent. When Brock explained his situation to Jordan, he received a round-trip ticket to Detroit for an interview with GM, and later a job offer. Brock later said, “GM was like going to the best grad school. The best education a car designer could hope for.” At 19 Brock was the youngest designer ever hired at GM.
Brock couldn’t have been happier and would often work after hours. One evening Design Director Harley Earl entered the design studio and struck up a conversation with Brock. Earl asked Brock what he thought of GM’s design direction. Surprisingly, Brock told Earl that GM needed to look into the small car market because the Europeans was making inroads and GM needed a small “student’s car” for young people that couldn’t afford a new bigger car. Earl was intrigued. After several more evening conversations with Brock, Earl informed Brock that he was starting the XP-79 Cadet project and that Brock was to lead the design effort, under the direction of a studio boss! What an astonishing opportunity!
Brock went through the entire design process, from sketches, and line drawings, to a full-size mockup that looked like a small European GT. Earl loved the concept and expanded it to include a delivery vehicle. But when Earl showed the $1,000 Cadet concept at Styling’s 1958 line review meeting, there was dead silence. GM president Harlow Curtice said, “We don’t build small cars at GM!” The project was dead, but it did plant a seed that soon became the Corvair.
Harley Earl was about to retire, and his Olds Golden Rocket-like C2 Corvette concept was going nowhere. Around the same time the 1957 AMA Racing Ban killed all racing activity. But 46-year-old Bill Mitchell was about to take over as VP of Design upon Earl’s retirement, and had his own ideas of what the next Corvette should look like. The main Chevrolet design studio was where official GM advanced production designs were created, but Mitchell also set up a special Studio X where he could do his own private design work. After returning from the 1957 Turin Auto Show, Mitchell gave his Studio X team photos of cars that most impressed him; the streamliner record cars from Abarth and Stanguellini, and the Alfa Romeo “Disco Volante” coupe. He liked the bulging fenders and sharp horizontal crease line, and instructed his team to sketch some ideas based on the photos.
A few days later, Mitchell came back to review his team’s progress. He carefully looked at all the drawings and stopped at one and said, “Whose work is this?” Brock raised his hand and Mitchell said, “Nice! I’d like everyone to take a closer look here because this approach to the theme has some real possibilities. Your goal is to expand on this. Let’s see how we can approve.” Studio head Bob Veryzer might have been peeved because he put Brock’s drawing away! But during the next review, Mitchell asked, “Where’s that sketch I approved?” Veryzer put the Brock sketch back up and Mitchell said, “Yes, that’s the one! This is what I want!” That’s how Brock got in the lead design team.
Brock refined his design and explored removable roof panels, unique door hinges, and a roll bar built into the B-pillar. Several weeks into the project, Mitchell asked Brock if he knew anything about Earl and Duntov’s 1957 SS Racer. Brock explained that he and several of his designer friends drove around the clock to Sebring to see the car race. Mitchell was impressed and then explained that he had acquired the SS mule chassis and intended to use it as a successor to Earl’s car, and work on it as an “advanced concept”. Thus the XP-87 was born.
Based on Brock’s refined sketches, a work-order was released for a 1/5th scale model to be built. Because of UAW regulations, all of the clay work would have to be done only by the modelers and Brock couldn’t even touch the model. What Brock learned was that the modelers were outstanding, fast professionals, and totally open to his sugestions; they were there to serve the designers. Once again, Brock was learning from the best.
Around the same time, Ed Colewas pushing his Q-Chevrolet line concept that would have all 1960 Chevrolet cars, including the Corvette, use a transaxle for better weight distribution, and to eliminate the interior transmission hump. Duntov’s engineering layout included an all-aluminum fuel injected engine, a four-speed transaxle, four-wheel independent suspension, a platform chassis, and inboard brakes. A full-size space buck was built and Brock and the team translated the 1/5th scale mode into a full-size clay model. Brock commented that with the space buck, everything fell into place. Unfortunately, the entire Q-Chevrolet concept collapsed due to cost and was diluted down to a less expensive car more suitable for production.
Peter Brock explains the Stingray Racer.
But Mitchell still was hooked on Brock’s design. The XP-87 project morphed into Mitchell’s Stingray Racer and then into the 1963 Corvette project, both driven by the capable skills of co-designers Larry Shinoda, Chuck Pohlmann, Tony Lapine, and Gene Garfinkle. Because of the AMA Racing Ban, Brock saw no opportunity to be involved with anything connected to racing, so he left GM on good terms, and went back to California to begin his racing career.
Post GM Brock raced an ex-Le Mans team Cooper and later upgraded to a Lotus II Series 2, coming in runner-up two seasons in a row to veteran racer Frank Monise. Through providence, Brock was Carroll Shelby’s first employee and set up the Carroll Shelby School of High Performance Driving, ran Shelby’s Goodyear Racing Tire operation, helped develop the very first Shelby Cobra. Brock also created the Cobra Daytona Coupe to take on the Ferrari, won an FIA GT World Championship, and World Speed Records at Bonneville.
In 1965 Brock started Brock Racing Enterprises and raced Hinos, Datsuns, and even a NASCAR Mercury until 1972. After Brock decided to end his racing career, he got into hang gliding. In recent years Brock has worked as an automotive photo journalist and authored a book about the Daytona Cobra Coupes, and “Corvette Sting Ray: Genesis of an American Icon. In 2017 Brock was initiated into the National Corvette Museum’s Hall of Fame in 2017. Brock Brock’s single sketch was the beginning of the Sting Ray. – Scott
Here are the links to the previous five parts of the “Corvette’s Founding Fathers” series…
Larry Shinoda: Genius Designer/Stylist and Self-Confessed Malcontent
Larry Shinoda was the perfect designer/stylist for GM VP of Styling Bill Mitchell. In the same way that Mitchell fit with Harley Earl, Shinoda clearly understood what Mitchell wanted. As VP of Design, Mitchell’s job was to hold the vision for what he knew would be new and fresh, then lead his designers and stylists to bring his vision into reality. Corvettes were always Mitchell’s pet projects and he was famous for saying, “Don’t get cocky, kid! I design Corvettes around here!” Mitchell’s Corvettes were about design, speed, power, and performance. And for that, he needed a designer/stylist equal to Duntov’s engineering/racing prowess. Larry Shinoda was his man.
Shinoda was a self-confessed malcontent, and proud of it. As a kid, Larry was always drawing cars with pencil stubs he found. At the age of eight, he did a large color painting that years later hung in the Los Angeles Museum of Art. Just after his father died when he was 12-years-old, Larry and his family were swept up and sent to a Japanese internment camp. No doubt that this helped form his surly persona. While in the camp, Larry designed and built a reclining chair for his grandmother from wooden crates. After two years of internment, Larry and his family relocated to Grand Junction, Colorado to help with the family nursery business. But rural life wasn’t for Larry and he quickly relocated back to Los Angeles to finish school.
Late 1940s California was the birthplace of the hot rod car culture and Larry was all-in! He built hot rod Ford coupes and roadsters called “Chopsticks Special” that he street raced, drag raced, and speed raced on the dry lakebeds of California’s Mojave Desert. When he wasn’t racing, Shinoda worked at the Weiland Company to put himself through two years at Pasadena City College. After college Larry had a two year stint with the Air National Guard and spent 16-months in Korea.
Shinoda knew that if he was ever to be a designer, he’d have to go to the Art Center of Design in LA. What seemed like a great idea quickly went sour, and Larry was kicked out! Shinoda only wanted to design cars, and saw no value in watercolor and life drawing classes. One of Larry’s former instructors called him when a rep for Ford was interviewing for designer positions.
Shinoda put together his portfolio and showed up for the interview in his attitudinal car-guy gear; peg-let jeans, and a loud Hawaiian shirt over a Howard Cams t-shirt. The Ford rep was so impressed with his work that Larry was offered a higher-than-normal salary, plus Ford paid to transport his hot rod to Michigan! But before going to Ford, in 1953 Shinoda set the SGTA Bonneville Nations D-Class Speed Record with a two-way average speed of 166-mph in his Chrysler-powered roadster. Then in 1954 Larry won the Fuel Roadster class at the first NHRA Nationals in Great bend, Kansas. Yes, gasoline was in his veins.
Shinoda spent a year with Ford learning the ropes of a big corporation and picking up a lot from fellow designers. Not contented with Ford, Shinoda jumped over to Packard where he befriended John Z. DeLorean. Earlier that same year, Larry was part of the John Zink crew that raced and won the 1956 Indy 500. Naturally, Shinoda designed the body and the car’s paint scheme. Shinoda and DeLorean quickly realized that Packard was a sinking and jumped to GM.
Hired as a senior designer by Harley Earl in late 1956, life inside GM was uninspiring. After his short orientation, Shinoda was transferred to the Chevrolet group where his unique flat rear fin design was incorporated into the 1959 Bel Air. Larry even showed how to manufacture the unique shape by welding the upper and lower parts of the shape and covering the weld with chrome trim. Larry then had a brief stint in the Pontiac design group and worked on the Wide Track Pontiacs and the 1960-1961 Tempests. To counter the doldrums in the Buick and Cadillac groups, Larry rendered the big cars with racing numbers, stripes, and mags. His bosses were not amused!
Sometimes providence has to bring the right people together. One day on the way home from work, Shinoda pulled up to a stoplight next to a supercharged 1958 Pontiac with VP of GM Design, Bill Mitchell behind the wheel. Larry let Bill get ahead of him, then totally smoked the VP! A few days later when Mitchell was in the Chevrolet studio, he asked who owned a white 1956 Ford. The studio boss said, “Hey Larry, don’t you have a white ’56 Ford?” Shinoda confirmed that indeed, he was the guy that dusted off Mitchell. Bill asked Larry to bring his car into the garage so he could check out the designer’s machine. When Mitchell looked under the hood, he nearly had a heart attack! The engine was a Bill Stropp race-prepared 352 with dual quads, headers, NASCAR shocks and a full roll cage. It was essentially a racecar! That was IT! Mitchell had found his go-to design/styling man.
Mitchell’s Studio X was the perfect place for Shinoda and it was there that he did all of the Corvette work he’s loved and admired for. Larry’s first project for Mitchell was to take Peter Brock’s 1957 Q-Corvette design and translate it to fit the mule chassis of the 1957 Corvette SS Racer. The result was the 1959 Stingray Racer. Mitchell erroneously thought the shape would act like an inverted airfoil and push the car down. The front-end lift was terrible and was unfortunately inherited by the C2 Sting Ray. Before the C2 Sting Ray project, since Shinoda had already designed the body of a winning Indy 500 car, he was tasked to create the body for Duntov’s Indy car-like CERV-I R&D vehicle.
Not only did Mitchell’s Stingray Racer win a championship, it was such a hit with the crowds, the design had to be the next Corvette, and Larry Shinoda was the man for the job. Translating a sketch into a racecar body is one thing; making the shape into a real automobile is a whole other thing. The only carryover parts were the engine and transmission, everything else had to be designed and styled. Although the Sting Ray was Mitchell’s vision, Shinoda and his team worked out the visual details.
Shinoda was the perfect man for the time. Design studios all over Detroit were white-hot with secret advanced design projects and a steady flow of concept cars. The following cars all have “Larry Shinoda” baked into their DNA, and they all still look good today; 1959 Stingray Racer, 1960 CERV-I, 1962 Corvair Super Spyder, 1962 Monza GT, 1962 Monza SS, 1962 Mako Shark-I, 1963-1967 Sting Ray, 1964 GS-2b, 1964 CERV-II, 1964 Rear-Engine XP-819, 1965-Mako Shark-II, 1966 Mako Shark-II, 1965-1966 and 2D, 1967 Astro-I, and the 1968-Astro-II.
Larry Shinoda was well rewarded for his contributions. Just before the Mako Shark-II project, Larry was promoted to Chief Designer for Special Vehicles, where he coordinated efforts with Frank Winchell’s Chevy R&D group and Vince Piggins Performance Group. But by 1968, the self-confessed malcontent left GM to work with his friend Semon “Bunkie” Kundsen, the new president of FoMoCo. Larry’s new position at Ford was Executive of All High-Performance and Show Vehicles. Shinoda was responsible for the Boss 302 and 429, the Torino Talladega, Cougar Eliminator, the King Cobra, the Torino Design Study, Cyclone Spoiler II, and the Mustang and Torino pace cars. But life inside Ford was more turbulent than GM, and after 16 months, Knudsen and Shinoda were fired. The Shinoda/Knudsen team then formed RV company RecTrans, which was soon bought by White Motor Company, with Knudsen as president.
The last chapter of Shinoda’s career began in 1976 when he created Shinoda Design Associates, Inc, with a staff of designers, clay modelers, technicians, engineers, and fabricators. Shinoda’s team worked to help client’s profitability with excellent design that would be appealing to their client’s; trucks, boats, motorcycles, golf equipments, products. Larry’s last Corvette project was the Shinoda/Mears Corvette body kit.
Larry’s older sister Grace had this to say about her famous brother, “Creative people take risks. They see things in new ways that the establishment doesn’t agree with.” She certainly knew her brother very well.
Larry passed on November 13, 1997, but on January 6, 1997 he completed and signed a color rendering of a C5 Corvette Split-Window Coupe with C2-style front and rear fender humps and rear bumper cover. Clearly, Larry wanted to see more “Sting Ray” in the then-new C5. Unfortunately, Larry health issues got in the way and the project never went past the illustration. The following year, Larry was inducted into the National Corvette Museum Hall of Fame. And in 1995 Larry was inducted into the Mustang Club of America’s “Mustang Hall of Fame”. Larry Shinoda was outspoken (often to his own determent), candid, humorous, and firmly believed in whatever he was doing. – Scott
and 2D, 1967 Astro-I, and the 1968-Astro-II. 
