2025 Corvette ZR1’s LT7 Is a High-Octane Dream V8

• The 2025 Chevrolet Corvette ZR1’s 5.5-liter DOHC V8 shares the same basic architecture as its less powerful LT6 version that powers the Corvette Z06.
  

• Chevrolet says this LT7 engine makes 1,064 hp and 828 lb-ft of torque while burning 93-octane gasoline.

• Chevrolet says the LT7 can rocket the 2025 Corvette ZR1 to 215 mph.

We are living in the golden age of performance. On the heels of the wild V16-PHEV Bugatti’s outlandish 1,800 hp, Chevrolet is showing off its latest Corvette ZR1.

Without any electric assistance, Chevrolet says this 5.5-liter V8 will send 1,064 hp and 828 lb-ft of torque through an eight-speed transmission to the rear wheels.

Foundationally, this LT7 uses the same architecture you’ll find under the LT6 engine cover of the current Corvette Z06. That means the same finger-follower valvetrain is triggered by a pair of camshafts over each cylinder bank.

But there are some major differences setting apart the LT7 from its naturally aspirated sibling. From the top, you’ll notice a new intake manifold.

As hard as it is to believe, this new twin-throttle-body intake manifold wasn’t inspired by the Rochester RamJet fuel injection system of Fulie fame, but it does kind of look the part.

While this new intake handles induction duties, there’s also a set of fuel injectors that supply all the fuel this Corvette wants—spraying directly into each cylinder—while doing a little charge cooling and giving GM engineers some flexibility.

Moving outward, the most obvious difference between these engines is the pair of 76-mm turbochargers that force air through those 65-mm throttle bodies on the LT7. These ball-bearing, mono-scroll turbochargers are affixed directly to the exhaust manifold to reduce the time it takes to spool the compressor.

Electronic wastegates manage the boost pressure, and an anti-lag system keeps some boost ready for when you crack open the butterflies.

Moving inward, Chevrolet engineers stuck with the DOHC design (do they miss the pushrods?), but the valvetrain has revised timing and lift relative to the Z06. These cams rest in cylinder heads that are also different from the Z06 and sport different combustion chambers. These new chambers help keep detonation at bay and reduce some static compression.

Prepping for the boost, the folks at Chevrolet dropped the LT6’s 12.5:1 compression ratio to 9.8:1, aided by new pistons. With a lower compression ratio, the air forced into the cylinders required 5-mm larger wrist pins and similarly larger connecting rods. The beefier wrist pins might not sound like much, but the difference is apparent when viewed side by side (seen above).

Those titanium connecting rods link to a steel flat-plane crankshaft. It was speculated the team at Chevy would pivot to a cross-plane design for a stronger crankshaft, but your ears will thank the folks who argued successfully to keep the flat-plane design. Four-bolt main bearing caps help keep the rotating assembly stable at 8,000 RPM.

All in all, this is an impressive effort from GM and Chevy, and this will likely go down in history as one of the most potent packages ever released by an automaker. Of course, you can read about everything else heading to the Corvette ZR1, here, but there’s no question the star of the show is this LT7 V8.

Do you think this ZR1 will join the ranks of legendary Corvettes? Tell us your thoughts below.