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From GM Authority Press Release

BY JONATHAN LOPEZ— NOV 25, 2019

In the move to an all-new mid-engine layout, the Chevrolet Corvette C8 also gains a brand-new powerplant. Dubbed the LT2, the new 2020 Corvette engine is a considerable upgrade over the C7’s LT1, with a number of improvements for more power, greater reliability, and higher efficiency as well.

However, that’s not to say there aren’t several similarities between these two V8 engines. For example, both are naturally aspirated and offer 6.2L of displacement. That said, the 2020 Corvette engine was specifically engineered for the C8’s midship layout, unlike the front-mounted LT1. For example, packaging between the two engines is markedly different, with the LT2 forgoing the LT1’s considerations with regard to forward visibility.

Delving deeper, we find the LT2 also offers improved lubrication over the LT1. While the LT1 did offer a dry-sump oil system, the engine-mounted dry-sump system used with the 2020 Corvette engine is a step above, with three scavenge pumps providing loads of lubrication, even during hard cornering. Chevrolet claims that the LT2 will maintain oil pressure at up to 1.25 G of lateral acceleration, which is critical for those C8 buyers looking to head to the track on weekends. What’s more, the 2020 Corvette engine also requires less oil overall, with just 7.5 quarts to top it off – a reduction of 2.25 quarts compared to the LT1.

The LT2’s pan-mounted oil filter and cooler assembly also comes with cored oil and coolant passages for a 25-percent increase in cooling capacity compared to the LT1. The LT2’s oil pan sports a low-profile design, which means the 2020 Corvette engine can be mounted 25 mm lower in the engine bay compared to the C7, thus providing a lower center of gravity and all the associated handling that entails. Furthermore, the pan comes with a high-pressure die-cast construction for reduced mass.

“Much of the LT2’s additional power can be attributed to how much better it breathes,” Chevy says. That includes the intake manifold, which is bigger and taller compared to the LT1, up to 14.1 liters from the LT1’s 11.1 liters. The intake uses a low-restriction design with identical 210-mm-long intake runners, unlike the unequal-length runners on the LT1. This improves output and increases flow, with three-percent power gains compared to the LT1’s intake manifold. The LT2 also uses an 87-mm throttle body.

On the other side of the combustion chamber, the 2020 Corvette engine comes with a ground-up exhaust redesign specifically tailored for the mid-engine application. This includes high-flow pipes and a four-into-one design with twisted runners that help to ease the stress of thermal expansion. The runners are all roughly 330 mm in length. The end result is a 1-percent power increase compared to the LT1.

The LT2 exhaust also has new catalytic converters, with one split-volume catalyst per cylinder bank. This is a simplification over the two cats used on the LT1, and makes for a more economical design overall. Additionally, the LT2 can activate the new exhaust-scrubbers earlier thanks to new engine tuning, thus lowering emissions by 25 percent.

The 2020 Corvette engine gets a new camshaft profile too, with an extra 1 mm of exhaust lift, now up to 14 mm. This matches the intake side, with increased duration for both profiles to take advantage of the engine’s higher flow. Critically, the LT2 has a very stable idle, even more so than that of the LT1, thanks primarily to a new wide-range air-fuel sensor (WRAF). Finally, Chevy says the LT2 retains variable valve timing, with 62 crank degrees of cam phasing authority.

First introduced with the 2020 Chevrolet Corvette Stingray coupe, the LT2 can push the C8 from 0 to 60 mph in less than three seconds when equipped with the optional Z51 Performance Package. Output is rated at an SAE-certified 495 horsepower and 470 pound-feet of torque with the upgraded performance exhaust system, making for the most-powerful entry-level Corvette ever produced. Muscle is routed through the M1L eight-speed dual-clutch transmission.

“The LT2 is one of our best efforts yet in Corvette’s history of naturally aspirated high performance Small Block V8 engines,” said GM’s global Chief Engineer of Small Block engines, Jordan Lee. “This engine is incredibly powerful and responsive. Power is readily available when the driver needs it.”
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For additional engine and transmission images of the C8 see C8 at Automobility show
 

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Jeff, great summary of the differences between those 2 engines. I'm sure trunk space was the driving factor for Chevy doing the exhaust pipes on the C8 where they are instead of a higher mounting like on the lambos.
 
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