wanting to swap a 3800 series 2 engine, out of a 95 camaro, into my 91 firebird...will the 3800 bolt to my to my 3.1 tranny

Nope. 3.8 is 90 degree. Snag the 4th gen trans and you've got a good start.

Snag the 4th Gen EVERYTHING. 3800 engine is OBDII with different components and harnesses than your 3.1. If you're seriously going to swap in a 3.8 out of a 4th Gen car, use everything including the harnesses, computer, transmission, and sensors. Exhaust may also be affected, since the Gen 4 3800 uses 4 oxygen sensors in the exhaust system.

In fact, I'm not sure that you could re-use your old exhaust manifolds or Y-pipe. I'm doubting it will work. You should grab the 4th Gen manifolds, Y-pipe, and catalytic converter. Your 3rd Gen exhaust should bolt on from there.

Emissions will play a factor with the computer. If you don't hook up the 4th Gen EVAP canister, purge solenoid, etc, you're going to end up with trouble codes and it may end up affecting the way that engine runs. OBDII is a huge pain.

Good luck...this swap is probably more amibitious than a V8 swap, if you do it right, thanks to the OBDII stuff....

don't forget the fuel tank.

Umm, guys, the 95 Camaro is NOT OBDII. It's OBD 1.5. It still uses an OBD I ECS with some modifications, namely the OBD II DLC, but it's still OBD I. OBD II went into effect for the 96 model year (Federal mandate).

However, to make the list short, he needs the engine, exhaust, emissions stuff, harness, wiring diagrams (for both cars, especially a C207 and C100 pinout), the 4L60 trans, and at least the fuel pump. However, like was said above, I would nab the plastic fuel tank as well and clean all of the crap out of it. And, while I was getting the trans, I would also opt for the aluminum driveshaft (provided the car has it).

Okay, you're right about it being OBDI/1.5. I thought I had read "96 Camaro" rather than "95."

Still, ojfox, you're going to require all of the same things that we have mentioned here. You're basically going to be rebuilding a 4th Gen car into a 3rd Gen body.

One more thought....swapping in the 4L60 transmission, will he be able to use the 3rd Gen transmission crossmember and mount, or will he have to go with 4th Gen components? I know that there is a difference between the two in terms of height of the tailshaft above the crossmember. The transmission mount from a 3rd gen will not bolt into a 4th Gen car (at least not on the V6 applications). Been there, tried that on my '98 with a urethane transmission mount. The mount didn't come close to fitting the '98, but it fit just fine on my '84.

And what about the radiator? Does the radiator for the 3.1 cars have the hose connections in the correct positions for the 3.8 engine's hoses?

Everything is possible. I put into my III-gen firebird 3800 series II engine and transmision from 2001 Firebird. There is a lot o work. I made new engine mounts, new y-pipe, modify crossmember, made new transmision mount, new exhaust etc. Now i'm making new harness. I'm going to mount radiators from IV-gen and other components. One of the most important troubles is how to made front ABS sensors and where i could instal AC compresor.

both engines share the same bellhousing pattern, you could bolt the 3.8 to the 3.1 trans.


as far as computers go, you could swap the OBD2 or 1.5 rats nest in but you should be able to find a harness and ecm from an older FWD 3.8 car that will run the 3.8 just fine, you can then tune it as well..