GM’s Parts Book strikes again. The proprietary listing used by technicians just confirmed the 2027 Corvette Grand Sport will get a 6.7-litre LS6 V8, settling weeks of speculation about the sixth-generation engine’s actual displacement.
The leak comes from the same source that revealed the C8 ZR1’s LT7 specifications back in 2023.
That earlier leak confirmed the twin-turbo 5.5-litre V8 with direct injection, variable valve timing, and active fuel management.
The accuracy of that information makes this new revelation even more credible.
The Parts Book listing describes the LS6 as an eight-cylinder 6.7-litre Generation Six aluminium overhead valve engine with both direct injection and port fuel injection.
That’s bigger than the widely reported 6.6-litre figure that dominated recent speculation.
A person close to GM independently confirmed the 6.7-litre displacement to Corvette Blogger, doubling down on the authenticity.
Previous reporting suggested GM was building two V8s for the sixth-generation family: a 6.6-litre and a 5.7-litre that would be shared between Corvette and Chevy’s truck portfolio. The new information changes that narrative.
The smaller 5.7-litre unit will likely power vehicles like the Chevrolet Silverado 1500.
The larger 6.7-litre engine gets tuned specifically for power and performance in the Corvette.
Expect to see it in other performance applications too, including a future Cadillac CT5-V Blackwing that could benefit from the extra displacement and power.
GM introduced the fifth-generation small-block V8 in 2013. The sixth-generation motor starts arriving in full-size pickups beginning in 2027 before rolling out to other models.
The automaker invested $579 million at its Flint Engine Operations in 2023 to build the new V8, then added more funding earlier this year.
GM promises the new engines will deliver more power than current offerings. The existing 5.3-litre V8 makes 355 horsepower and 383 lb-ft of torque.
The larger 6.2-litre produces 420 horsepower and 460 lb-ft, with the supercharged version reaching 682 horsepower and 653 lb-ft.
The power increase won’t hurt efficiency either, according to the automaker. Whether GM pairs the engine with any electrification remains unclear.
The company is pulling back from some EV efforts, but hybrids continue growing in popularity. Some vehicles will likely feature electric assistance.
The leak was found under a listing of future RPOs for the 2027 model year.
GM apparently learned their lesson about including future Corvette models ahead of release after the ZR1 leak, but the RPO codes gave away the goods anyway.
Recent video footage captured the sound and rumble of the new sixth-generation engine, reinforcing excitement around the legendary LS6 designation returning to the Corvette lineup.
