Chevrolet Performance launched the naturally aspirated 6.6L V8 L8T crate engine back in December, offering up the same capability provided by GM’s heavy-duty pickup trucks, but with availability to those customers looking to build their own project vehicle. Now, we’re getting a few insights into what makes the L8T what it is, courtesy of the following brief feature video.
Hosted by Design Release Engineer, Chevrolet Performance, Blake Nye, the video launches into an overview of the technical aspects of the naturally aspirated 6.6L V8 L8T crate engine. The L8T was originally available in the 2020 Chevy Silverado HD and GMC Sierra HD, and as such, was built to handle the demands expected of those two nameplates.
Based on the Gen V LT engine platform, the atmospheric L8T was designed to make loads of twist in heavier applications, such as pickup trucks and SUVs. The block is made from iron, with displacement rated at 400 cubic inches, or about 6.6 liters. The cylinder bore is 4.060 inches (103.25 mm), while the stroke is 3.860 inches (98 mm). Interestingly the L8T offers the largest displacement available in the Chevrolet LT engine family.
“The L8T produces more torque at the bottom end to mimic older engines, as opposed to the high-revving LT1 and LT4 options,” Nye states. Peak output is rated at 401 horsepower at 5,200 rpm and 464 pound-feet of torque at 4,000 rpm on 87-octane pump gasoline, while the maximum recommended engine speed is set at 5,600 rpm. The compression ratio is set at 10.8:1.
Fueling is courtesy of high-pressure direct injection (2,175 psi / 150 bar). The L8T also does not include active fuel management. The engine does, however, incorporate variable valve timing with two overhead valves per cylinder. The heads are made from aluminum, and are based on the production engine. The intake manifold also incorporates long runners for extra low-end twist.
If you’re thinking about grabbing the L8T for your project, or just want a quick overview of what it has to offer, this video could be just what you’re looking for: