Corvette Chiefs, Pt. 2 of 5 – Dave McLellan

Dave McLellan, Heir to Duntov’s Engineering Throne

(Dateline: 7-3-20 – This story was originally published in the now-defunct Vette magazine, July 2019 issue. Story, Illustrations & Graphics by K. Scott Teeters) – When Dave McLellan took over as Corvette’s new chief engineer on January 1, 1975, it was a whole new world. The prevailing trends went from performance cars to safer cars with reduced emissions. Not even Duntov could have made a difference in the ‘70s. But as performance went down, Corvette sales went way up! The sales department was happy, but the Corvette was really getting old. Dave McLellan was an unknown to the Corvette community and many wondered what he would bring to the brand. It turned out; he brought a lot!

McLellan was a car guy. He rebuilt his family’s Frazer and entered the Fisher Body Craftsmen’s Guild Model Contest. Upon graduation from Wayne State University in Detroit with a degree in mechanical engineering, GM hired Hill on July 1, 1959. Thought the ‘60s Hill worked at the Milford Proving Ground on noise and acoustics issues with GM tank treads, Buick brakes, and tuned resonators for mufflers. Hill was also going to night school to get his Master’s Degree in engineering mechanics. In 1967 Hill was part of the group that planned and operated the 67-acre Black Lake where ride, handling, and crashworthiness tests are performed.

Chevrolet engineering brought in Hill to work on the 1970-1/2 Camaro and Z28. Hill wanted to move into management so he took a yearlong sabbatical and attended MIT Alfred. P. Sloan School of Management. The school emphasizes innovation in practice and research. In July 1974 Hill was Zora Arkus-Duntov’s part-time assistant, training for taking over the position in 1975.

While Hill didn’t have Duntov’s racing experience, he owned several Porsches and understood racing sports cars. As Duntov was leaving, he told Hill, “Dave, you must do mid-engine Corvette.” Little did they know that it would finally happen forty-five years later.

When Duntov took control of Corvette engineering in 1956, he had to boost sales and make the Corvette a performance car and a capable racecar. When Hill took control, Corvettes were never selling better, but the platform design was nearly fifteen-years-old. Hill had to keep the car fresh, hit the new requirements, and maintain performance; all with a limited budget.

Management figured that the Corvette had a captive audience, so they didn’t have to spend money to change anything. Fortunately, that lame notion was overruled. The 1978 glass fastback and the 1980 front and rear bumper covers were excellent updates. Another major issue was quality control. The St. Louis assembly plant made three other cars and often workers were unfamiliar with the specialties of the Corvette. This issue didn’t get fixed until the plant was moved to the Corvette-only Bowling Green facility.

McLellan knew that the C3 needed to be replaced, as the chassis was designed around 1960! For a brief period, it looked like the mid-engine Aerovette would become the C4, but Chevrolet decided to abandon all mid-engine programs. The all-new C4 began to take shape in Jerry Palmer’s Chevrolet Studio Three in 1978. When the C4 debuted in December 1982, it received rave reviews, despite the fact that suspension engineers later admitted that they over-did-it with the stiff suspension. By 1985 the suspension was softened and the 150-mph Corvette won Car and Driver’s “Fastest Car in America” award and began the total domination of Corvettes in the SCCA Escort Showroom Stock racing series from 1985-to-1987. Porsche bought a Corvette to take apart to find why the car was unbeatable. By the end of 1987, SCCA kicked out all of the Corvettes for being too fast! McLellan followed up with the Corvette Challenge factory-build racecars.

McLellan’s personal style was more suited to the intricacies of modern electronic computer-controlled performance cars than Duntov’s. Where Duntov’s enthusiasm was effervescent, McLellan was laid-back, approachable, but not shy with the automotive press. After the successful rollout of the C4, McLellan took on four very serious performance projects for the Corvette; The Callaway Twin Turbo option, the ZR-1 performance model, the LT-5 Lotus/Mercury Marine performance engine, and the mid-engine CERV-III. Let’s look at all four projects.

“Supercars” were the rage and by 1985 Porsche had their 959 and Ferrari was about to unleash their F40. To have something to offer while McLellan was starting his ZR-1 project, a deal was made with Reeves Callaway to build brand-new Corvettes with a Callaway Twin Turbo package. The cars had 345-horsepower (stock Corvettes had 240) and from 1987-to-1991 RPO B2K was the only non-installed official RPO Corvette option ever offered.

The ZR-1 super-Vette had two components. The first was its Lotus-engineered, all-aluminum, double-overhead-cam engine built by Mercury Marine. McLellan’s engineers set down the size parameters and horsepower objective; Lotus did the rest. McLellan turned to the best manufacturer of all-aluminum, performance marine engines in the country, Mercury marine. The end result was the beautiful jewel-like LT-5, an engine that is still respected today. The second component was the widening of the ZR-1’s body to cover the enormous P315/35ZR17 rear tires and beef up the car’s drivetrain and suspension.

The 1990 CERV-III Corvette was McLellan’s vision of Duntov’s mid-engine Corvette, with electronic steroids. The car had a carbon fiber Lotus-style backbone chassis, four-wheel steering, active suspension, a transverse, 650-horsepower twin-turbocharged LT-5 ZR-1 engine and a dry-sump oil system, and a four-speed transaxle. This was the final design that started out as the Indy Corvette in 1986 and had a top speed of 225-mph. And lastly, the CERV-III was designed to be manufactured.

Photo: GM Archives

When McLellan was part of the 1992 “Decision Makers” three-man internal Chevrolet design group, gathered to evaluate the direction of the C5, McLellan chose the CERV-III concept over the front-engine “Momentum Architecture” and the stiffer/lighter restyled C4. But the CERV-III was deemed too expensive for the market. The “Momentum Architecture” with its backbone structure, a transaxle, and an all-aluminum engine with design elements from the LT-5, lives on today in the C7.

McLellan oversaw the three-year, 1990-to-1992 mid-cycle refresh. The process started in 1990 with an all-new dash; 1991 saw new front and rear bumper covers; and in 1992 the 245-horsepower L98 was replaced with the 300-horsepower LT1.

In 1990 McLellan won the Society of Automotive Engineers’ Edward N. Cole Award for Automotive Engineering Innovation. In 1991 GM was offering early retirement packages, allowing 53-year old employees to receive the same benefits as those retiring at 62. McLellan took the offer and stayed on as a consultant while GM looked for a suitable replacement. McLellan was fortunate enough to be in his consulting position on July 2, 1992, when he was on hand to see the one-millionth Corvette roll off the Bowling Green assembly line. What a thrill for a car that McLellan had given so much to and a car that was so often on the line for its survival.

Finally, on November 18, 1992, the new chief of Corvette engineering was Dave Hill. Since then, McLellan has been a much sought after automotive consultant, he wrote and illustrated “Corvette From the Inside” and he’s a frequent and revered guest of honor at all of the top Corvette events. In 1999 McLellan was inducted into the National Corvette Museum’s Hall of Fame. McLellan goes down in the Corvette history books as the second of the five great Corvette chief engineers. – Scott

PS – Be sure to catch all 5 parts of my Corvette Chiefs Series

Corvette Chiefs, Pt. 1 – Zora Arkus-Duntov

Corvette Chiefs, Pt.2 – Dave McLellan

Corvette Chiefs, Pt. 3 – Dave Hill

Corvette Chiefs, Pt. 4 – Tom Wallace

Corvette Chiefs, Pt. 5 – Tadge Juechter

 


 

 

 

 

Corvette Chassis History, Pt.4: The C5 Chassis That Dave Hill Built

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

Corvette Chassis History, Pt 1 – C1 Chassis – HERE

Corvette Chassis History, Pt 2 – C2/C3 Chassis – HERE

Corvette Chassis History, Pt 3 – C4 Chassis – HERE

Corvette Chassis History, Pt 4 – C5 Chassis – HERE

Corvette Chassis History, Pt 5 – C6 Chassis – HERE

Corvette Chassis History, Pt 6 – C7 Chassis – HERE

 


 

 

Corvette Chassis History, Pt. 3: The C4 Chassis That McLellan Built

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

Corvette Chassis History, Pt 1 – C1 Chassis – HERE

Corvette Chassis History, Pt 2 – C2/C3 Chassis – HERE

Corvette Chassis History, Pt 3 – C4 Chassis – HERE

Corvette Chassis History, Pt 4 – C5 Chassis – HERE

Corvette Chassis History, Pt 5 – C6 Chassis – HERE

Corvette Chassis History, Pt 6 – C7 Chassis – HERE


 


The Story of the ZR-1 Corvette – C4 1990-1991 ZR-1 Corvette: Part 2 of 4

1990 ZR-1 Corvette – Finally! A Dedicated “Performance” Model Corvette

Dateline: 8.11.17 – Photos: GM Archives, Michael Beal, Illustrations: K. Scott Teeters – There’s an unwritten, unofficial “Law of the Jungle” that basically states, “If you are at the top of the food chain, you might not be there for long.” Such was the case for the C4 ZR-1 Corvette, for a little while. The C4 ZR-1 had a six-year production run with only 7,018 units produced. The ZR-1’s head-exploding price was the biggest limiting factor. The crummy economy in the early ‘90s didn’t help, and the much-rumored, all-new C5 no doubt was a drag on the ZR-1’s sales. And then there was also that pesky Dodge Viper. The 427 Cobra’s “Marley’s Ghost” was obvious, only this time disguised as a Dodge,
 
While armchair quarterbacking is easy and hindsight is 20/20, it is worth asking the question, why wasn’t such an awesome car more successful? “Timing” aside, the ZR-1’s aesthetics was a big factor. Stated simply: When viewed by itself, the C4 ZR-1s look like “regular” Corvettes. As an illustrator and stylist, I find it astonishing that Chevrolet would have done this, after all the engineering work that went into the ZR-1.   The body panels from the doors all the way back to the rear bumper cover, are unique to the ZR-1 – made wider to cover the widest tires put under a factory-built Corvette body, to that point. This means that the panels had to be redesigned. But rather than make them visually unique, the Corvette stylists were commanded to imitate the basic design of the standard Corvette, with one exception   Continue reading


The Story of the ZR-1 Corvette – C4 1990-1991 ZR-1 Corvette: Part 2 of 4″


Corvette Timeline Tales: August 31, 1992 the 2nd Corvette Chief Engineer, Dave McLellan retires

August 31, 1992 – Dave McLellan accepts early retirement and steps down after 18 years as the Corvette’s second Chief of Engineering.

8-Dave-Mclellan
General Motors had a mandatory, “retirement at 65” policy, so as Corvette Chief Engineer Zora Arkus-Duntov was nearing retirement in January 1975 the big question was who would be chosen to fill Zora’s big shoes.
Duntov was not consulted about his replacement and McLellan would not have been his choice, but Dave was definitely the man for the job. McLellan was an Alfred P. Slone Fellow with a degree in engineering and management. The ‘70s was not a fun time and there were serious issues to be dealt with besides horsepower, racing, and mid-engine designs. There were emissions and quality control issues, as well as the implantation of a new assembly plant and an all-new Corvette to be designed and developed.

1990-ZL-1
Along with ushering in the Corvette into the digital age of computer controls and guiding the design and development of the C4, the ZR-1 was arguably one of Dave McLellan’s biggest achievements.

When the C4 Corvette came out it received rave reviews – “The Best Vette Yet!” and under McLellan’s leadership kept getting better and better every year. By the late 80s, performance was back to late 1960s levels, Continue reading


Corvette Timeline Tales: August 31, 1992 the 2nd Corvette Chief Engineer, Dave McLellan retires”


Wil Cooksey’s 2013 Interview on Scott Teeters’ Far Out Radio Program

Wil Cooksey shares his life story and career in GM and building Corvettes.

Wil-Cooksey

Dateline: 8.29.15 – Yesterday we told you about the 2015 Corvettes at Carlisle show and that Wil Cooksey is one of the special guests for the event. Actually, ever since Wil put on that stunning, explosive burnout display back in 2007, he’s become an almost permanent fixture of the Corvettes at Carlisle show.

On April 5, 2013 I had the pleasure of interviewing Wil Cooksey on my Far Out Radio program. The YouTube version of the program is below.


Continue reading


Wil Cooksey’s 2013 Interview on Scott Teeters’ Far Out Radio Program”


Corvettes At Carlisle 2015 is Corvette Enthusiast Sensory Overload

The Biggest Corvette Party on the East Coast is ON!

Corvettes-At-Carlisle-2015.

Dateline: 8.28.15 Corvettes at Carlisle is one of the top three Corvette events. The annual four-day event is situated on 82 acres, in beautiful, rural south east Pennsylvania, just down the road from the Carlisle Army War College. The 82 acre fairground is in a huge bowl shape with “Corvettes only” in the infield. It is absolutely, Corvette sensory overload!

Special guests include…

Was the 1984 Corvette Really That Awesome?

Dateline: 7.24.12

An alternate look at the lowly 1984 C4 Corvette.

Be sure to CAST YOUR VOTE for your Favorate C4 Corvette, HERE.

The Illustrated Corvette Series continues on with its look back at the “first” of each generation Corvette. The latest issue of VETTE (November 2012) covers the first C4 1984 Corvette. It’s hard to believe that it was 29 years ago this summer that Dave McLellan and his team stunned the automotive press at the ‘84 press preview with the all-new ‘84 Corvette. I can sum it up with one expression, “Heads spun!”

Now, if are new to the Corvette hobby, you most likely know that as of today, an ‘84 Corvette is arguably the lowest valued Corvette on the market. But when you look back and read the reports and road tests, one can’t help but ask, “How could that be?!?” The quick answer is that the reason this happened was because the C4 Corvette improved so much, so fast. While the platform of a ‘96 Corvette (the last year for the C4) is the same, it might as well be a different car.

In the C4’s 13 model year run, here’s a short list of the big items that changed:

* Front and rear bumper covers, wheels and tires, front fender vents. Continue reading “Was the 1984 Corvette Really That Awesome?”

Corvette Pace Car Files: 1986 Indy 500 Pace Car Corvette

Dateline: 10.7.11
A Look Back at the Most Common and Overlooked Corvette Pace Car 

1986 was a banner year for Corvette fans with the return of the roadster. The ‘70s was an awful time for performance cars and “fun” cars in general. Between new strict emission controls, sky rocketing gasoline prices (all the way up to 50¢ a gallon! in ‘73), reduced performance, and increased safety concerns, it was not a good time. Convertibles also went down the drain too. Beginning in the Fall of ‘75 with the ‘76 model, there were no more Corvette roadsters. After 22 years, the Corvette Roadster was dead.

So in ‘85 when it was announced that the roadster would be returning, Corvette fans couldn’t be happier. But unlike the olden days when a convertible Corvette cost LESS than a coupe (the ‘75 convertible cost $6,550 and the coupe cost $260 more than the roadster!), the ‘86 Corvette convertible cost an additional $5,005! Unlike the C2 and C3 chassis and body structure, the C4 was not originally designed to be a topless car. Coupe to convertible conversions usually have the characteristic cowl shake and sometimes ride more like wiggle wagons where the driver can actually see the dash shake on bumpy twisty roads. The solution for the C4 was to add a large X-brace to stiffen the chassis.

The second piece of big news for ‘86 was that a Corvette would pace the Indy 500 for the second time. Retired General Chuck Yeager was enjoying celebrity status as a result of the book and movie, “The Right Stuff.” But Chevrolet was still smarting from the heavy criticism over the ‘78 Corvette Pace Car debacle and seemed to go in the opposite direction. Rather than producing a set number of pace car relicas, ALL ‘86 Corvette convertibles were designated as a “Pace Car Replica” and came with dealer or customer applied decals for the doors. Many said, “Why bother.”

By the end of the year, 7,315 of the 35,109 Corvettes were convertibles (20%), all considers “pace cars” regardless of the color of the car. The actual Indy 500 Pace Cars were all yellow and 732 yellow convertibles were sold for the year. No special embroidery, wheel centers, stripes, spoilers… just a set of decals. Consequently, of the six Corvette pace car replicas offered from ‘78 to ‘08, the ‘86 model is the least valuable. Most of the ‘86 Corvette convertible “Pace Cars” never had their decals applied. Continue reading “Corvette Pace Car Files: 1986 Indy 500 Pace Car Corvette”

1996 LT4 Small-Block Chevy – The Finished Classic SBC?

Dateline: 9.30.11
Forty One Years of Classic Small-Block Chevy Success and Power!

When the Cadillac-derived Small-block Chevy engine first arrived in 1955, I’m certain that Ed Cole and his team of Chevrolet engineers never imagined that their efforts would have such a profound and long lasting impact on the automobile industry. The little 265-cubic-inch engine had just 162-horsepower. By 1970 the 350-cubic-inch LT-1 engine was packing 370 gross horsepower. Beginning in 1973 Gm started rating their engines in “net” figures making it look as if the legs had been cut out from under all of their motors. While it’s true that there were emissions restrictions and reduced compression, the “net” power ratings were in real-world terms, closer to reality. From ‘73 to ‘96 it was a long slow slog, but the last SBC to use the basic original design was the 330-horsepower LT4. So, what would be the ”gross” horsepower rating of a ‘96 LT4? That would be anyone’s guess, but somewhere close to or over 400-horsepower would be a good guess.

Since Spring ‘11 I have been asking the question in my Illustrated Corvette Series VETTE Magazine column, “What’s the best _____?” for each generation Corvette. ICS No. 174 takes a look at the 1996 LT4 Corvette and asks, is this “The Finished Classic SBC?” let’s get into the details. Talk about going out with a roar! Enjoy – Scott

Illustrated Corvette Series No. 174: 1996 LT4 Small-Block Chevy – “The Finished Classic SBC?”

The ‘97 C5 Corvette was introduced to the press in November ‘96 at Road Atlanta Raceway, in Georgia and went on sale at Chevrolet dealers on March 7, 1997. Not only was the body, interior, chassis, and suspension all-new, there was a totally new engine and transaxle. The splash the new C5 created, followed up with roadsters, Pace Cars, hardtops, race cars, and a Le Mans win in ‘01, was so huge that the highlights and achievements of the C4s quickly faded. While the jewel-like LT-5 that powered the exotic ZR-1 still stands as the high watermark of the C4 generation, there was a quieter high watermark that took place. Had the LT4 engine option arrived a few years before, there would have been another Chevy legend.

The C5 program was an on-and-off-and-on again project due to GM’s financial troubles in the early ‘90s. Initial sorties began in ‘88 with the intention of an all-new C5 a ‘93 model. Corvette chief engineer, Dave McLellan was given a budget of $250 million, but that number turned into a roller coaster ride with the C5 being pushed back year after year. GM’s miracle of the ‘90s was that there even was a C5 Corvette. All of this makes the LT4 even more amazing. Continue reading “1996 LT4 Small-Block Chevy – The Finished Classic SBC?”

Corvette Timeline Tales: August 26 – 28, 2011 – 30th Anniversary of Corvettes at Carlisle Show!

Dateline: 8.27.11
Corvettes here, there, and everywhere. CORVETTES as far as the eye can see!

It all began on September 26, 1974 when friends Bill and Chip Miller rented the Carlisle Fairgrounds for their first old car parts swap meet. Some 600 vendors rented 800 spaces and over 13,000 car enthusiasts paid $1.00 each to attend. Year after year, Chip and Bill kept improving their operation. In 1981 the Millers bought the 82-acre parcel of land and not only created a local landmark, but established an enterprise that brings in $97 Million dollars to the local economy. Carlisle, Pa has never been the same since!

Being Corvette enthusiasts to begin with, Chip and Bill didn’t need much coaxing to launch a Corvette-only show in August 1981. Over 25,000 Corvette lovers attended to see over 2,000 Corvettes, and a new Corvette tradition was born. Since then everyone who’s anyone in the world of Corvettes has been to the Carlisle show: Zora Arkus-Duntov, Dave Mclellan, Dave Hill, Larry Shinoda, Wil Cooksey. race car drivers including, John Fitch, Mario Andretti, Dick Guldstrand, Tony Delorenzo, artists including Dana Forrester, Dan McCrary, and the list goes on and on.

If you have never been to the Carlisle, let me describe the facility. The first thing that you are aware of is that the place is HUGE! Carlisle is located in the rolling hills of south east Pennsylvania in what is known as “Pennsylvania Dutch Country.” The town of Carlisle dates back to 1751, but is most known for the Carlisle War College that dates back to 1904. Carlisle is also known for the Carlisle Indian Industrial School that was started in 1879. After you enter the fairground, if you look around, you’ll see that the facility is situated in a very large bowl-shaped area. For the Corvettes show, Carlisle productions only allows Corvettes to park in the infield. So, when you are inside, all you see are CORVETTES. Aside from a few trucks and support vehicles, everywhere you look, you see CORVETTES. After four or five hours, it’s sensory overload. “Oh look! Ah, just another ZR1!”

Building T is where you’ll find the “Chip’s Choice” feature Corvettes. Every year there’s a different theme. For 2011 the theme was “Corvette Barn Finds.” Everyone loves a good barn find story, so why not a collection a lost and found old Vettes – patina dirt and everything. In previous years Chip’s Choice has featured Corvette race cars, movie cars, retro rod Vettes, and more. Continue reading “Corvette Timeline Tales: August 26 – 28, 2011 – 30th Anniversary of Corvettes at Carlisle Show!”

A Turbocharged Blast From the Past – the 1979 Experimental “Turbo Corvette”

Dateline: 8.22.11
Before the Callaway Twin Turbo arrived, Corvette engineers were taking a shot at turbocharging a 1979 Corvette

 

To see the much larger image from the September/October issue of VETTE Magazine, click the image.

The C7 Corvette rumor mill has been quiet the last month of so. Oh, a few weeks ago there was a burp about a possible C7 chassis mule hidden under a late model Corvette Coupe. (not much in that report) Then towards the end of May ‘11 CorvetteBlogger.com posted a report from TheDetroitBureau.com that the C7 would be powered by a turbocharged 3.0-liter V8. Of course, no one really knows except for the Chevrolet and Corvette engineers that are working on the project. But my take is that the little turbo engine report is pure speculation. There have always been those that have wanted the Corvette to be a small European-like sports car. I say, if that’s what you want, buy a Lotus.

Will Chevrolet back down from the 638-horsepower high-water-mark of the current LS9 engine? Let’s hope not. The computer emission controls on the latest LS engines seem to be more than capable of adjusting for horsepower, as we’ve seen from the work of Howard Tanner, the new “Mr. Motion” that’s building the official authorized, 800-horsepower  Baldwin Motion Phase III Camaros. (Yes, I have it on excellent authority that a Phase III C6 Corvette is in the works.) What might pull the plug on a mega-horsepower C7 Corvette power plant is the CAFE (Corporate Average Fuel Efficiency) standards. But since Corvettes are a tiny percentage of the average of all GM cars, they might be able to slip in a horsepower beast into the C7 to function as their latest, greatest halo car. It’s ALL up in the air and delicious fodder for bench racing.

To see the much larger version and read the story from the September/October issue of VETTE Magazine, click the above image

But the turbocharged issue is interesting and got me to remembering an earlier turbo Corvette that Chevrolet was tinkering with. Back in 1979 the above show car Corvette was powered by a 195-HP L48 engine with an AIResearch tubrocharger that bumped the power up to around 280 – 290-HP. Why they didn’t use the more stout L-82 engine, only the Corvette engineers know. Ask Dave McLellan if you get the chance. But the extra 90-to-100-horsepower didn’t WOW anyone in the already husky ‘79 Corvette. But the car sure looked cool! The silver Coupe wore production front and rear spoliers, Continue reading “A Turbocharged Blast From the Past – the 1979 Experimental “Turbo Corvette””