For years, Chevy’s factory-backed Corvette race cars have been delightfully anachronistic, running old-school pushrod V-8 engines with cross-plane crankshafts. But this is the dawn of a new era in Corvette. The mid-engine C8 is just about to hit the streets, and now, Chevy has unveiled the mid-engine C8 race car. Meet the C8.R, with an all new engine that’s decidedly unconventional—at least by Corvette standards.
At a press event at Road Atlanta ahead of this weekend’s Petit Le Mans, Chevrolet introduced journalists to the all-new C8.R race car. The most notable news—aside from the new midship location of the powerplant—has to do with the engine that will power this new race car. The C8.R runs a naturally-aspirated 5.5-liter V-8, just like the last car, but now featuring a flat-plane crank and dual overhead cams.
Corvette engineers didn’t give much detail beyond that. They were willing to say that the engine makes around 500 hp and 480 lb-ft of torque, though the actual output will fluctuate based on Balance of Performance adjustments throughout the 2020 racing season. The new DOHC engine is direct-injected, and coupled to a six-speed sequential gearbox from X-Trac that was redesigned to make more room for the substantial diffuser at the rear of the car. The engine has the conventional intake and exhaust layout (intake in the inside of the vee, exhaust running outboard), and Corvette representatives were quick to emphasize that the engine is not substantially related to Cadillac’s Blackwing, a 4.2-liter hot-inside-vee twin-turbo V-8 that puts out 550 hp and 627 lb-ft of torque in the production CT6-V.
Of course, one of the favorite traits of previous C5.R, C6.R and C7.R race cars was their signature exhaust note—a loud, raucous, deep V-8 rumble that was especially notable compared to the high-pitched sounds of European competitors. Fans loved it, especially at venues like the 24 Hours of Le Mans, where the Corvette’s rumble felt distinctly American.
So far, the C8.R prototypes we’ve heard have had a distinctly different aural signature. Asked about how the switch to a flat-plane-crank, overhead-cam engine would impact the C8.R’s exhaust note, Corvette chief engineer Ed Piatek said, “I think we’re still gonna have a signature Corvette sound, and you’ll know it coming over the hill before you see it, it just might not be the same sound we had in the past. I think it sounds like nothing else I’ve ever heard.”
Corvette officials wouldn’t answer any questions about whether we might see this 5.5-liter DOHC engine in a future production car, but that seems all but inevitable. As we pointed out last week, FIA LM GTE homologation rules state that an engine “must be derived from a series production engine produced at more than 300 units and fitted to a series vehicle from the same manufacturer.” Now that the production Corvette has gone mid-engine, a switch to flat-plane crank and overhead cams could be in the works too.