The Mercury News

Flying Car Mode and other secrets of the 2020 Corvette Stingray

- By Mark Phelan

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.

Corvette wanted to move the engine from the nose to behind the passenger compartmen­t. Called midengined, that arrangemen­t lets cars use more power than the traditiona­l front-engine 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.

Plans to build a mid-engine Corvette were closely held even within GM. Around 2014, the team built a cardaccess 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 car-based 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-a-kind “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 midengine ‘Vette was again under considerat­ion. It immediatel­y became the top target for spy photograph­ers, who specialize in getting pictures of vehicles automakers are developing.

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 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.

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.

The optional adaptive Magnetic Ride Control shock absorbers talk to the Corvette’s traction control system, a feature that comes in handy at high speeds on the track, vehicle performanc­e manager Alex MacDonald said.

Why? Because when a car goes airborne at very high speeds, normal traction control senses the rear wheels spinning and responds as if they were on ice or another slippery surface: It slows them.

That’s a handy feature in normal driving, but slowing the powered wheels costs you time on the race track. That’s why, in performanc­e traction mode, the front shocks communicat­e that they’ve got no weight on them meaning they’re in the air. The rear wheels will inevitably follow, but the traction control is told to ignore it and keep sending power when they start spinning, because it knows all four wheels will be on the ground again momentaril­y. The result, a quicker lap time.

Memory for obstacles

Front bumpers and air splitters that hug the ground look good and improve performanc­e, but they’re easy to damage on steep driveways and tall parking blocks. The Corvette’s suspension can raise the nose an inch to avoid such obstacles.

An optional feature called GPS-based front lift can remember up to 1,000 spots where you raised the nose. When you approach one, it raises the nose an inch at up to 25 mph.

A front camera can also be used to look down from the nose to spot obstacles when parking.

2020 Corvette Stingray fun facts

74% of orders so far are for the coupe, 26% for the convertibl­e, which doesn’t go into production until April.

The most popular color is Torch Red.

GT2 seats with carbon fiber trim are most popular.

There are 2,600 C7 Corvettes left at dealers, expected to fall to 2,000 by March 1.

“Corvette Academy” features 24 videos on the 2020 Stingray’s developmen­t and features.

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