A recent GM leak may have just revealed a major secret about the upcoming Corvette Grand Sport, offering fans a glimpse at what could be a transformative addition to the C8 lineup.
The iconic Chevrolet Grand Sport nameplate is expected to make a return for the 2027 model year, and new details suggest that under its hood, a completely new engine could be waiting to excite enthusiasts.
Rather than modifying the Stingray’s 6.2-liter naturally aspirated V8 or scaling down the Z06’s 5.5-liter flat-plane-crank engine, GM might introduce an all-new powerplant for the Grand Sport, reportedly called the LS6 V8.
For years, information about this engine has been scarce, with rumors pointing to possible 5.5-liter and 6.6-liter configurations.
However, a leak from the GM Parts Book, used by technicians for vehicle diagnostics and repairs, indicates the LS6 may be even more potent than expected.
The leak shows the LS6 will displace 6.7 liters (409 cubic inches), featuring an aluminum block and dual fuel injection, both port and direct.
Notably, the same GM Parts Book was instrumental in revealing the C8 ZR1’s 5.5-liter twin-turbo V8 back in 2023.
Earlier this month, Corvette insider and salesman Rick Conti shared a YouTube video that reportedly captured the new Grand Sport’s exhaust note.
Although the clip was removed after a few days, it suggested the LS6 will deliver a classic, throaty V8 sound, a detail certain to thrill Corvette enthusiasts.
The exact output of the 6.7-liter engine remains unknown, but GM has plenty of room to position it between the entry-level Stingray and the hybrid E-Ray in the C8 lineup.
The Stingray’s performance exhaust produces 495 horsepower, while the E-Ray is rated at 655 hp, and the Z06 delivers 670 hp. Chevrolet could find a sweet spot for the Grand Sport in the range of 550–600 hp.
Pricing is likely to be strategic as well. With the Stingray starting at $70,000 and the E-Ray at $108,600, positioning the Grand Sport between $85,000 and $100,000 could make it the ideal balance of performance and value, appealing to a broad spectrum of buyers.
If executed well, the Grand Sport could even become the volume leader in the C8 lineup.
