GM’s Beloved Line of Small-Block V-8s Is Reborn Once More With the LS6

Some things are fundamentally part of American culture. Baseball. Apple pie. Catchy advertising campaigns. And small-block Chevrolets.

For only the sixth time since the small block came to the Corvette in 1955, General Motors announced the all-new small-block V-8. Known as the LS6, this new 6.7-litre unit perfectly blends the small-block formula of yesteryear with the brand’s most up-to-date technology to create a truly powerful beast worthy of the LS name. For this reason, Road and Track To better understand what exactly makes this new V-8 so powerful and why GM decided to revive an old name for a new engine, GM spoke with Mike Kociba, deputy chief engineer for small-block engines.

For those keeping score at home, this isn’t the first time GM has used the “LS6” name on a Corvette V-8. The first of these was a big-block engine introduced in 1970, with a massive displacement of 454 cubic inches; It was the largest engine ever installed in a Corvette. The first small-block bearing the LS6 nameplate entered in 2001 C5 generation Corvette Z06. A heavily reworked LS1, the 5.7-liter V-8 produced up to 405 hp in Corvette trim. 6.7 liters (or In terms Brian Wilson might prefer, 409 cubic inches) lies exactly between the two engines in terms of displacement. According to GM, this isn’t exactly an accident.

The increased displacement over the Stingray and E-Ray’s previous 6.2-liter V-8 wasn’t just for performance. The team found that the 6.7-liter engine gave the team fewer compromises when it came to emissions and fuel economy; especially when paired with the “Displacement on Demand” system, which will be crucial to keeping the V-8s naturally aspirated once the program launches. Things may have changed a bit since then, but this approach still benefits customers in terms of efficiency and performance.

Like every small-block before it, the LS6 features the iconic 4.4-inch bore centers. The engine has a larger stroke than the previous model, now sitting at 100mm versus 92mm. The engine also gets some old-school hot rod parts, including forged rods and pistons, a larger 95mm throttle body, high-speed ports for the fuel system (now powered by port and direct injection), and a massive tunnel ram intake on top. The lubrication and cooling systems have been completely reworked, with highlights such as dual main oil feeds for the bottom end and two-piece water jackets in the cylinder head to help protect the valve train. The LS6 also has an impressive 13:1 compression ratio, higher than any small-block before it, including the days of leaded fuel.

Part of the reason GM has been able to push the engine this far is based on its new engine management system, known internally as “Encantado.” The name is taken from Brazilian folklore and refers to a shape-shifting cryptid. This is an apt name, as the system relies on machine learning to help speed up testing and improve it over time. LS6 marks the first V-8 application of the software.

Because of how significant all of these changes were, GM felt it was time to move away from the “LT” name. The brand adopted the LT nomenclature when the C8 arrived because it helped emphasize that this wasn’t your grandfather’s Corvette. Seven years later, they thought it would be appropriate to make this distinction once again. LS was a natural landing spot.

“If you look at small-block history, you will see that we use a lot of RPO,” Kociba said. “A lot of our RPOs carry a lot of heritage and connection with our customers. So when you hear an LS and an LT, you immediately know it’s a performance car.”

“We don’t choose an RPO on most of our engines, but we always do for small-blocks because they make sense for our customers,” he added. “We wanted to honor our heritage and we wanted to pass on their race [pedigree] and the feeling of performance. So we chose to go back to LS. You could also say, ‘we reintroduced port fuel injection and the Gen Four had port fuel injection’, so there’s some synergy there. That’s how we got the first part – LS. And then six, really… this is the sixth generation [engine]”

“It felt appropriate to launch this product with the LS6.”

While the LS6 engine is coming to the Corvette for 2027, the architecture is sure to spread across the GM lineup in the coming years. While it’s unlikely that future pickup trucks and SUVs will get the full 13:1 compression ratio and tunnel-cylinder intake layout, it’s still expected to be a solid improvement over the 6.2-liter engine currently offered. (Customers will definitely welcome the new engine as well, Considering the reliability of the 6.2s is not fully known.) I’m happy to see an LS V-8 available again. I can’t wait for a chance to test it myself. especially when it reaches Stingray in 2027.

You may also like

• If You Can Only Have One Car, Make It One of These

• These Are the Most Popular Cars by State