LIL D

why does the 93 cobra estimate at 235 but the gt40 crate motor estimates at 345 i know the heads are dif but what makes it some much diferent

tjmon1

The 93 cobra motor is very under rated. It's actually closer to 300 HP. The gt40 crate motor you are looking at is probably aluminum with other upgrades. I have a gt-40 crate motor (cast iron) in my 86GT and it was rated 285 with stock intake and 65mm TB and headers.

LIL D

the setup im using is a 306 with cobra inake e303 cam 1.7 rockers and either e7thumper heads or gt40heads what kinda a power am i looking at and wil lforged alum pistons handle a 100 shot

dman302

240-260 to the wheels..no on the juice that is.

gspfunk

Forged pistons are better for spray and boost. Safer and less likely to fail, anyway.

tjmon1

240-260 sounds about right. The gt40 heads will be cheaper than the e7 thumpers. I have heard great things about thumper port jobs. As far as juice goes, I have no Idea with aluminum pistons. I had a zex135 shot on my last mustang I owned and it was a stock 93GT.