Hey guys havent been on here in a while, i started to rewire my Firebird(87, lG4) Now it has a 350 crate and i dont need any of the smog, egr computer stuff, its got a vac advance distributor, and and old stlye guages. So i can cut the rest of the harness out right, except lights and what not?

 

The problem with doing that is that the main harness (engine harness, not the smaller one running to the front of the car for the headlights) also includes the wiper harness, reverse light switch (for T5 cars), the VSS signal wires, power wires to the dash and to the headlight module from the starter and the alternator, the coolant fan wiring, the ignition wiring (still got to have power going to the coil from the switch, right? Don't forget the tach, either), and some of the A/C system wiring (if have it and you're keeping it). All of which means you would literally have to pick through each and every wire in the harness to cut out the ECM controls. And not just at the big connector at the firewall, either.

 

https://www.thirdgen.org/forums/ltx-...p-3rd-gen.html

Everything you need to know to cut what you dont need out of your stock harness.

 

i just got through with doing that same thing. cut out what you think you dont need, but leave 12 inches or so of each wire on the fender side of that big weatherproof plug (dont know the technical term for it) on the right side of the car. just in case you have to rewire something later. (i didnt do that, that was my mistake.)

you'll be surprised at just how much **** you'll be able to pull out of the engine bay. ive got an entire box full. i wish i took a before and after pic. lol. ive only got the after