​​An All-New 6th Generation Small Black V8 to Debut on the 2027 Corvette​

The Corvette has been on the market continuously since 1953 and is now in its eighth design generation. The Chevrolet small-block V8 debuted in 1955 and was immediately installed under the Corvette’s hood, as well as in Chevrolet’s classic sedans of the day. Unlike the Corvette, the small-block has had only five design generations, but a sixth-generation engine will launch for the 2027 model, replacing the current LY2 6.2-liter V8. Twin Falls Chevrolet provides some details on this new engine. 

Dubbed the LS6, the engine will be a naturally aspirated 6.7-liter V8. It will be the standard engine for the 2027 Stingray, and for the return of the Grand Sport and Grand Sport X. If the LS6 name sounds familiar, that is because it has been used for two prior GM V8 engines. It was first used for the 454 cubic-inch (7.4L) big-block V8 that filled the hoods of high-performance Chevrolet models from 19740 to 1976, including the Corvette, as well as the Chevelle, Caprice, Monte Carlo, and El Camino. The name returned for the third-generation small block that appeared on Corvette Z06 and Cadillac CTS-V models from 2001 to 2005. 

GM brought back the name to reflect the small block’s sixth generation, but this new engine carries more heritage than just the name. Its 6.7-liter displacement translates to 409 cubic inches, echoing another iconic Chevrolet V8 immortalized by a Beach Boys song titled “409.” As a chef’s kiss, the LS6 will be assembled at GM’s Flint Engine Operations in Flint, Michigan, returning production to the city where the first small-block V8s were built in 1955. 

In addition, the increased displacement results from a stroke that was lengthened from 92 mm to 100mm.  This means that the current cylinder bore of 103.25 remains, and the engine retains the same 4.4 inches between cylinder centers that GM small blocks have had for seemingly forever. 

The engine will produce 535 horsepower at 6100 rpm, more than any standard Corvette engine has ever produced. In addition, its 520 lb-ft of torque is the highest torque ever produced by a naturally aspirated V8 GM engine. 

“We’re trying to recreate some of what worked in the muscle-car era,” says Mike Kociba, Assistant Chief Engineer for the Small Block. “We wanted a wide, high torque band, and high power. It feels like we’re bringing a piece of Americana back.” 

Interestingly, the engineers originally aimed for 6.6 liters – another GM engine displacement immortalized in song, but found through modern digital engine design tools,  stretching to 6.7 liters created more power with no fuel mileage penalty. 

“We were going to make it ‘only’ 6.6 liters, and then we started playing around and realized that by adding two millimeters to the stroke, we get more performance without compromising anything else,” Kociba said. “In the past, we might not have explored that.” 

Another key to the engine’s performance is its 13.0:1 compression ratio, which is the highest ever for a Corvette.  The team specifically wanted to beat the 12.5:1 compression ratio of the L88 big-block V8, which was built primarily for racing but was available on the 1967-69 Corvette.  That engine had the benefit of the internal baffling created by tetraethyllead in the gasoline to prevent pre-ignition.  “The only way we could pull off beating that today with unleaded fuel was with our advanced controls.” Says Kociba. 

What else Chevrolet will do with this engine in the years to come, we can only speculate, but for now, the LS6 represents the start of the sixth generation of Small Block V8S, extending a legacy more than 70 years in the making.  Look for the LS6 when the 2027 Sting Ray and Grand Sport models arrive at the Twin Falls Chevrolet inventory this fall.