This article will describe the components and details of a 396 cubic inch LT1/LT4 for a supercharged application. It’s based on a combination I’ve built many times, intended for use with a centrifugal blower such as a Vortech S-trim or T-trim, or a Procharger P-600 or D-1. It has very good drivability, and will make 600 RWHP on premium pump gas at 12 psi while using a good intercooler. With race gas, an aftermarket computer, and 18 psi, this same combo has run 9.50’s at 145 mph in a very well prepared street/strip Camaro.
Lets get to it….
At the heart of the rotating assembly will be a forged 3.875″ stroke crankshaft with standard size 2.100″ rod journals, 350 main journals, and a 1 piece seal rear flange. This configuration isn’t widely available, and given the power level that’s attainable, I’d certainly recommend sourcing a reputable American made company. If you plan to step up to a cog style belt, you should consider having your crank custom made with a Big Block Chevy post. Just be aware that this option requires a special timing set, timing cover, and damper.