Brycelago

Hello I have an 88 iroc....right now I'm in the process of rebuilding just got my rear disk conversion brand new k member replica corvette wheels....basically my plan is over the next couple of months I'm getting the blueprint 383 crate motor it's 430 horse and then after I get that I'm gonna do a t56 swap....I'm wondering what I need to do to turn this into a 12 second car what gears I need to run in the rear also what suspension upgrades I need to make the car safe to handle all that power and torque

AlkyIROC

Back when I had a 383, I ran 12.0 with 3.27 gear, TH350 trans and 3800 stall converter on slicks. Gearing was all wrong but the engine put out close to 500hp.

What gears you need depends on a lot of factors. Tire height and engine rpm range determine what gears are required. If geared properly, you'll cross the finish line at the top of your rpm range in high gear (not OD) or you'll be wanting to shift just before the finish line. You should be in high gear by the 1/8 mile mark. The last 1/8 mile is a high gear brute HP pull to the finish. If you don't get enough RPM to peak out at the finish line then you need a deeper gear in the diff.

An engine that makes peak power at 5800 rpm will want different gears compared to an engine that makes peak power at 7000 rpm.