LONG- Need some advice (2002 motor with 1998 harness) hear me out
This will probably be moved to Conversions and Hybrids, but please leave it here as your answers will probably help me more.

I have a 1998 Firebird, it came with the V6. I basically blew up the V6 with a turbo kit, yadda yadda yadda--

Bought a 2002 LS1 motor w/ harness/pcm, etc, everything.

At that time, I didn't know the EXTENSIVE wiring differences between the 98 year model and everything after.

Since my car is wired as a 98- it will be very hard to get the 2002 wiring harness/pcm to adapt to the console/fuse box harnesses, gas tank, everything.

This is what I was considering--- hear me out:
Using the 2002 LS1 motor/tranny, and hooking it up to a 1998 LS1 wiring harness/PCM. This would make the swap 10x easier- HOWEVER, I don't know if I can hook the newer motor to the 98 stuff.

I know there are some basic changes throughout the years- EGR, fuel tank, fuel delivery system, cam, tuning, small things...

But I know the 98's and '02's uses the same injector size, so that wouldn't be an issue. Anyone have any insight on this- I'd really appreciate it.

Mostly just wanting to know how easily I can adapt a 2002 LS1 motor to using a 1998 LS1 harness/pcm.

-2002 LS6 Block, LS6 intake, LS1 heads, etc.
-Thunder Racing 215/220 .600/.523 115 "Old Man" Cam
-Titanium Retainers, Crane Double Valve Springs
-4L60E Transmission
-2002 Plastic Fuel Tank (Complete assembly w/ pump, lines, etc)
-2002 LS1 Gauge Cluster

If fueling would become an issue, I also have the stock V6 tank which is metal, 98 style, with the fuel return lines. I know I would probably need a new fuel rail, since I have the 2002 version.

 

I believe that the gauge cluster will need the BCM from a 2002, I think that the engine has a few different sensor plugs on it from 99 on up also but I'm not sure about that. I do know that the pinout on the 98 harness to the PCM is different than the 99 and up models.

Hope you can get the right answers, maybe a quick call to Speartech. He could make the proper harness for you.

Dale

 

The best way to do it is to have speartech or another wiring company of your choice use the 2002 harness and convert it so it will be basically plug and play with your interior harness and your v6 fuse box and all. I think I should know considering I put a 2000 in my 98. Hope this helps

 

dude theres nothing like factory just order a 98 engine harness to jive with the factory inside wiring. i bought a new harness for mine for 256 bucks

Jeremy