I just had a crate motor put in my 91 z28. It's a 383 with first fuel complete setup. The motor came from precision auto machine and was dynoed at 386 hp and 494 ftlbs. I had a local shop do the swap and everything went well. The engine came with the computer that was tuned for the setup. The problem is that at first it fired right up and sounded great and then began running rough and stalled. The cooling fans never came on and it ran too hot so we shut it down. It idles erratically and then keeps shutting off. The fuel pressure is set to 40 psi as per instructions, but after shutting off goes down. The mechanic switched to the stock computer and everything runs fine, including fans. He thinks the computer is the problem but before i send it back i thought someone here may have an idea of something i might be overlooking.
He has'nt tried driving the car on the stock computer, i'm afraid something will go wrong.

 

Wow thats interesting I want that same engine..Keep us updated

 

i just got word from the mechanic that the fuel pump was bad. He put on a used pump and it ran great. He ordered a new msd inline pump, Thank god i decided to not use an in tank pump! I also spoke to precision auto machine and they are going to send me another chip with the fans set to come on lol. I also told them about the lockup converter and to make sure to have that set up. The mechanic also ordered a jegs direct fit radiator. I should have the car next week, I'll try to post pics as soon as i can.