3.0L to 3.8L help!!!

[JohnAnthony]

I'm hopin that some1 here, can offer some help, guides and ideas. I own 2 Black 1986 2dr Grand AM SE both with 3.0L. (1 4 parts). And by lookin at this website. I'm going 2 assume thats a rare thing 2 hav 1, let alone 2. I started a project 5 years ago with the parts car (as a test). And that was 2 put a series I 3.8L under the hood. I never finished it. Which is a shame cause the 3.8L motor cost me $1900. I bought it from Jasper Engines. And I painted and polished it 2. What stopped me was it ran ruff, never smooth. I bought ALL new sensors, 3.8 injectors, and triple checked the firing order. All was fine. And yes I was running it off the 3.0L computer. And then I had to figure out how to mount the Alt and throttle cables. All were different. So has any1 seen this done b4? I would like 2 finish this. But I've about gave up hope. So right now I'm thinking of just rebuilding my 3.0L and putting it back in. But does any1 kno if there r performance parts 4 this 3.0L motor? Cam, Valves, Pistons, etc.........? Dependin on what help can b offered. That will decide what direction I go. 3.0 or 3.8.

[Brad97GS]

I would imagine that a big part of the problem is that you are still using the 3.0L engine's computer. You'd probably have to try splicing in a computer for a 3800, but that could be difficult given that it'd be from a completely different car. Otherwise some sort of piggyback computer system may work...? I'm sure it can be done, but I don't know exactly what needs to be added.

AFAIK, there are no performance parts specifically for the 3.0L. You can get general stuff, like a K&N filter, but I've never seen anything for this engine.

[ViperDVMan]

For any engine swap, I would always try to get a hold of both an ECM and a wiring harness from the donor car, or at least one with the same engine. I think your absolute best solution is to find another car with a Series I 3800 with the same type of tranny (manual or auto) as yours, and swipe its wiring harness. Do be aware of any cruise control features that may be on either your car, the donor car, or both, since that adds extra wires to the ECM. That should cure most of the problems.

Hope that helps.

[nineteen88ga]

holy thread revival.....

Just a question..the 3.0 motor mounts are the same as the 3.8 mounts? does that hold true for all the 3.8's up till now...3800 Series 3 S/C?