GM’s New L8T V8 Truck Engine is Just Begging to be Modified
There’s no replacement for displacement, especially with a new pushrod V8 on the horizon.
Do you ever see a new car and think, “I can’t wait to see one of those hit the auction so I can yank the engine out!” Well, that’s what ran through our minds when we heard about General Motors’ L8T V8. The pushrod V8 will start out life as the standard engine in the 2020 Chevrolet Silverado HD. The new engine will displace 401 cubic inches, or 6.6 liters. Naturally, Chevrolet is going for “low-end torque” and “improved towing capacity” but we’re thinking that’s just a starting point. LSX Magazine recently laid it all out in an excellent write up.
First, the L8T makes 401 hp and 464 lb-ft of torque with all that displacement. Keen observers will note that the big V8 is down on power a touch compared with the 6.2-liter “L86” engine found in the GMC Sierra 1500 (among others). The smaller engine makes 420 hp and 460 lb-ft of torque, thanks to an 11.5:1 compression ratio, while the L8T makes do with a 10.8:1 compression ratio. Why? The 6.2-liter needs premium gas while the 6.6-liter V8 can be run on horse piss 87 octane. Makes sense for an option that’s being introduced to improve torque and towing figures.
An important detail lies buried in the LSX Mag write up: “Because this engine is aimed directly at low-speed torque generation, GM added a forged crankshaft to its list of inherent advantages. Along with forged rods and hypereutectic pistons, strength is added with the use of an iron block.” You read that right: forged. Right after that, the author points out that the L8T will be missing the cylinder deactivation bits. This engine seems poised and ready no matter what direction you take it in. Forced induction? Forged internals and a lower-than-usual compression ratio lend themselves to the effort. Traditional engine building? A more aggressive cam, higher compression pistons, and some exhaust work should give the L8T a serious bump.
Though it’s still early in the process, what project would you throw GM’s big V8 into?