BRASELTON, Georgia—When Chevrolet unveiled its new “C8” generation Corvette Stingray in July, the headline was that after more than 50 years, the engine in this new car had been moved from ahead of the cockpit to just behind it.
At the end of that reveal, we then got a very brief glimpse of a heavily camouflaged racing derivative.
On Thursday, ahead of this year’s season finale to IMSA’s WeatherTech Sportscar Championship at Road Atlanta in Georgia, Corvette Racing gave us a proper look at that new race car, which is scheduled to start racing next year here in the US and also over in France at Le Mans.
Why did they move the engine?
If you look at a race car from Formula 1, IndyCar, or the prototypes that race in IMSA and Le Mans’ top class, you’ll find their engines located behind, not ahead, of the driver. The mid-engined layout really came to the fore in the early 1960s, when John Cooper’s eponymous F1 team proved that the layout conferred some significant handling advantages. With the engine fully ahead of the rear axle, most of the car’s weight is between the wheels, which makes for a much lower polar moment of inertia. And as the majority of the mass is toward the rear, there are traction advantages for the driven rear wheels.
None of this is to say that a front-engined car can’t be fast—since the team’s inception in 2000, Corvette Racing has racked up more than 100 wins here in the US, plus eight class victories in the 24 Hours of Le Mans, all with front-engined cars. Indeed, the current generation Corvette race car, the C7.R, still took 1st and 3rd in the 2018 championship. So why the big change?
“I think the story for both the streetcar and the race cars is that we really reached the limits of performance with the front-engined architecture,” explained Ed Piatek, chief engineer for the Corvette at Chevy. “We really needed to do something revolutionary to sort of take advantage of the physics of having more of the weight of the vehicle on the driven axle.”
Not just marketing, but also tech transfer
Racing is important to Corvette on a number of levels. From a marketing perspective, racing against—and beating—the best from more exotic rivals like Ferrari, Porsche, Aston Martin has done an awful lot to sell Corvettes. In fact, Corvette Racing was the only General Motors’ factory-backed racing program to survive the company’s government bailout following the 2008 recession.
However, the value of the program extends beyond PR. As I explored in some depth a few years ago, three successive generations of Corvette race cars really have led to concrete improvements in the road cars, transferring technology from track to street. For this new generation, the development of race and road Corvettes has been deeper than ever. “Starting back six years ago, when I started working on the new Corvette, we had Corvette Racing engineers in the meetings with us as we laid out the basic bones of the car,” Piatek told Ars.
What are the specs?
When Piatek says this car is all new, he means it, even down to the engine. The road-going Stingray (the sole street variant we’ve seen so far) uses one of GM’s venerable pushrod V8s. The C8.R on the other hand gets a brand new V8. It’s a 5.5L displacement—the maximum allowed under the IMSA and Le Mans rulesets for the GT category—but it features double overhead camshafts and a flat-plane crankshaft, which means it’s going to sound very different on track when compared with the throaty rumble we’ve been used to from racing Corvettes past. It’s also a direct-injection design, a decision that Corvette used on the C6.R racer but which had to be dropped from the C7.R.
Now, the ruleset that the Corvette was built to requires the cars to be derived from road-going versions. But currently, GM doesn’t have a flat-crank, direct-injection, DOHC V8 in its road cars. At first, I thought maybe it was a racing version of the “Blackwing” V8 that Cadillac has designed for its CT6-V sedan. But that’s almost certainly not the case.
No one from Chevrolet or Corvette Racing would elaborate much further on the new engine, although Corvette Racing program manager Doug Fehan told Ars that the new engine “has been homologated,” and it’s highly likely that a version of this engine will appear in future higher-performance C8 Corvette road cars in the coming years. That road car will almost certainly be more powerful than the C8.R—the rules require engine air restrictors (literally funnel-shaped devices that narrow to a required diameter) to prevent the race cars from getting too fast. So the race car is actually only around 550hp (410kW) and 480lb-ft (650Nm).
The C8.R is still going to be a lot faster than the road car around a track thanks to all the other race-specific changes. The engine sends its power to the rear wheels via a new six-speed sequential gearbox from Xtrac, which met Corvette Racing’s packaging and weight-distribution needs and which allows for a large rear diffuser under the car, critical for developing that all-important downforce. Inside the car, there are actually three fuel tanks: the two saddle tanks as found in the road car and a third located inside the chassis’s structural spine that runs down the middle of the car.
Up front, there are even more changes. Since a race car doesn’t need to worry about luggage space—at least not since the GT1 ruleset from the late 1990s—the Stingray’s frunk is now home to a large radiator. In the road car, the front radiators are mounted just ahead of either wheel; for the C8.R, you’ll instead find massive LED headlights that supplement the main headlights, a must-have considering that the C8.R will contest endurance races that don’t stop when the sun sets. And this car features the most unusual front splitter I’ve ever seen on a race car, with a number of strakes at its midpoint that channel the air to the right bits of the aerodynamic underbody.
What’s it like to drive?
Unfortunately (for me), the one question I really want to know is also one I’m unlikely to ever get an answer for firsthand, as Corvette Racing is wise enough not to let normies like me drive its race cars. That honor will belong to Tommy Milner, who shares the #4 Corvette Racing car with teammate Oliver Gavin. Milner has already had plenty of time in the C8.R during the car’s test program, and with so much experience in the C7.R, who better to tell us about the differences now that the engine is behind rather than in front?
“It’s obviously a different experience for us as drivers. It’s something that you notice maybe for your first couple laps, and then that’ll kind of fade and it’s just the car you drive and then you focus on understeer and oversteer, and how do I go faster, and how do I make the car go faster,” Milner told me. “It is fun to drive for sure. There are a lot of characteristics of the car that are still new, obviously. That makes it kind of more fun in some ways. We’ve driven the C7.R now for a number of years, and now having tested the C8.R a little bit, it’s fun to have something new.”