Corvette finally delivers mid-engine Stingray
LAS VEGAS — Evading helicopter surveillance and channeling the spirit of the “godfather of the Corvette” were business as usual for GM engineers developing the 2020 Chevrolet Corvette Stingray, code-named C8 because it’s the eighth-generation of the sports car.
The first mid-engined production car in Corvette history, the new Stingray had near-mythic status before it ever turned a wheel, and has won nearly every major new car award since it debuted in 2019. The first production models will arrive at dealers in late February or early March.
Chevrolet engineers and designers wanted to make a midengine ‘Vette since at least 1960, when legendary engineer Zora Arkus-Duntov led creation of Chevrolet Engineering Research Vehicle No. 1, or CERV I. Zora, a brilliant engineer and racing driver who transformed the 1950s Corvette from a car that was lovely but slow into America’s great sports car, wanted to move the engine from the nose to behind the passenger compartment. Called mid-engined, that arrangement lets cars use more power than the traditional frontengine layout because the engine’s weight over the rear wheels keeps the tires from spinning when the driver floors it.
“We could add horsepower, but we weren’t making the car faster,” chief engineer Ed Piatek said of front-engine Corvettes.
Through the decades, GM engineers and designers created one proposal after another for mid-engine ‘Vettes. None made it to production.
After a saga like that, it’s no surprise the 2020 Corvette Stingray generated stories of its own.
‘Nothing to see here. I’m just an Australian pickup.’
Plans to build a mid-engine Corvette were closely held even within GM. Around 2014, the team built a card-access only room inside an already-secure corner of GM’s tech center for the first prototype. Code name Blackjack, the two-seater hid the C8’s chassis and suspension under what appeared to be the body of the Holden Ute, a sporty carbased pickup made by GM’s Australian brand.
“It was a convenient shape to hide a mid-engine layout,” C8 lead development engineer Mike Petrucci said.
The only actual Holden parts on Blackjack are the brand’s chrome badge, headlights, outside mirrors and taillights, but the ruse worked. The one-of-akind “mule,” as development vehicles are sometimes called, served for two years of development drives — frequently at night, so not even other GM engineers would see it — at GM’s proving grounds in Milford and Yuma, Arizona.
Building Blackjack — by hand, of course — took eight months. The interior came from the C7 Corvette that was in production. Its body panels were handmade fiberglass, carefully shaped to look like a Ute while covering the C8’s bones. Those bones, incidentally, were milled from 7,000 pounds of aluminum ingots, work done secretly at other GM facilities.
In addition to Blackjack, the C8 team considered mules that looked like station wagons and vans, two other body styles that would allow them to hide the fact that the engine compartment was behind, not in front of, the passengers.
‘Incoming. Hide the ‘Vette!’
Despite GM’s secrecy, rumors leaked out that a mid-engine ‘Vette was again under consideration. It immediately became the top target for spy photographers, who specialize in getting pictures of vehicles automakers are developing. Confirmation that a mid-engine ‘Vette was coming, and good photos of the fabled project, could make somebody’s career, not to mention a stack of dough higher than the car.
In addition to staking out GM’s proving grounds and areas automakers develop vehicles — Death Valley in the summer, Finland in winter — some photographers hired helicopters to fly over the Milford proving grounds. Buzzing Yuma was verboten, its air space restricted because of nearby U.S. military installations.
By this time, Blackjack had been replaced by mules that, while still disguised, were clearly for a two-seat sports car. A single clear photo would let the cat out of the bag.
The answer was a better bag: A fabric car cover designed to be folded and stowed between the development car’s seats. You can hear helicopters before you see them in Milford’s wooded, rolling landscape. Development drivers were told to keep the windows open a crack, pull over, leap out and unfurl the car cover over the mule at the first sound of rotors. They drilled to perfect covering it quickly and refolding the cover precisely for fast deployment next time.
They succeeded, standing next to the covered car and waving at choppers overhead on at least a dozen occasions.
A wing like no other
A close look at the tall black wing rising above Blackjack’s tailgate reveals that it’s upside down, the exact opposite of the profile you see on race cars. While most automotive wings generate aerodynamic downforce — air pressure that pushes the vehicle down so it doesn’t leave the ground at high speed — Blackjack’s wing actually creates aerodynamic lift, like a plane’s wing.
That’s because wind tunnel tests showed Blackjack’s cobbled together body had aerodynamic lift at the nose. That’d be unacceptable in a production car, but since Blackjack’s body would never be built, the only thing that mattered was that its aerodynamic profile be equal front and rear. Creating downforce would be the production body’s job.
In addition, the two stanchions supporting the wing double as air intakes to cool the engine mounted under what appeared to be a tonneau cover on the pickup bed.
The C8’s performance targets — speed, aerodynamics, braking, fuel efficiency, etc. — were set during hundreds of thousands of computer tests before Blackjack was built.
What would Zora do?
GM had never built a car like the C8, so the engineering team had to invent many processes on the fly.
“At every turn, we asked ourselves, ‘What would Zora do?’ “Piatek said.
Arkus-Duntov, widely called the godfather of the Corvette because he led the car’s development for an unprecedented 20 years, pushed the performance envelope at GM from the day he joined the company in 1953, first and foremost by making Corvettes faster and better.