I just bought a LT1 from a 1996 Impalla with 95k. Gotta great deal, whole thing for $300, the guy put in a new engine wanted that one out of garage.

But I have two questions...one, i own a 89 Iroc-z that has the original 305 TPI in it. Can I just buy a stand-alone LT1 wire harness and that would work? and if so is it reconmended or not?

Plus i was wanting to know where can I get my hands on LT1 computer, and does anyone know who makes a good rebuild kit, and im trying to get about 400rwh, about my goal, because I will be driving this car a lot and dont want to kill myself in gas all the time if you know what i mean.
Thanks guys for imput!!!!

 

I'm thinking Z28***** said he could build a standalone harness, I used an f-body harness myself and made my standalone harness where I could unplug the LT1 harness from it without cutting up the LT1 harness or my dash harness for the GTA. You can always get LT1 PCM's on Ebay, but I would recommend getting a '95 PCM since it's OBDI and takes tuning easier. With 95k miles, I wouldn't worry about rebuilding unless it's knocking and smoking, put a decent cam in, or check out the Lloyd Elliot packages and you can get it close to 400hp pretty easily.

 

Yes I can make a harness if you are interested.

You have several options, going with what people refer to as a "standalone" harness really just puts you at the point of someone else with a stock 4th gen engine harness but the wires labeled, just getting the diagrams for the pinouts of the connectors will get you just as far and save you money.

After you have a stock harness or a "standalone" harness you need to either extensively rework a stock thirdgen harness to hookup to the engine harness, since the power wiring, relays, etc is all tied into the engine harness on a thirdgen.

The harness you start with affects where your pcm is mounted, using an F body harness leaves you with mounting the pcm in the a/c box area, or with minimal extending, you can get it above the relays and C100 connector, still not very optimal IMO. Using an Impala/Caprice harness allows the pcm to be mounted in the battery tray area of the drivers side, requiring only changing the mounting of the evap canister. Either harness requires a large amount of work to get it to fit properly and everything to function properly in a thirdgen IMO.

Your other option is a full custom harness from scratch, which I could provide you with, mounting the pcm in the stock location inside the dash, taking the factory route through the fenderwell. Or if you really want to be creative, technically speaking I could put it wherever you want.

 

if your looking for a good place to get info about making horsepower, go to ls1tech.com, there is a great deal of info there about lt1s.......im currently researching an lt1 swap into my 85 iroc, and when it came to mods ls1tech was a big help to me

 

hey z28 I changed out my motor to a 350 from a 305 h.o. both are tpi. My question is why am i not getting any injector pulse it started with this problem in my 305 and i thought it was the motor but come to find out later that it wasnt. can you give me any tips or maybe know what is wrong. I am trying to stay away from a carb, although i bought a carb and intake already. Anything would help fellas. Sorry to jump in on ya thred man, just had a ques, hope u dont mind.

 

Z28

I sent you a PM.

 

I also used an LT1 from a Caprice, but did not have the PCM or harness for it. So, I bought a harness and PCM from Howell Engineering, and it worked great. It cost me about $700 total. Here's the website:http://www.howellefi.com/shop/customer/home.php

 

You could have saved a ton of money making one yourself or having z28R@cer do one for a cheaper price. I have talked to him and hes indeed a lt1 swap harness guru, knows every wires function pretty much off the top of his head.