ok so i want to swap an ls6 into my 91 Z and i want to swap out everything old. when it comes to wiring harnesses i was wondering if the engine harness also controls all the accessoriers like headlights tail lights interior guages etc...?? if not then where could i buy a new harness that controls all of those?

 

no, painless or some other vendor for the chassis harness.

 

What is the problem with the existing body harness..? I would think you should be able to integrate the two where needed if the 91 body harness is still good.

The engine harness doesn't control (for the most part, anything relate to the body. A/C and a gauge or two) anything in the body harness. But nothing you really have to swap out the whole body harness for.

Check with some of the 3rd gen guy on what can be just integrated.

 

ok thanks. ya my factory harness is fine i was just wondering if itd be easier to just get a new one seeing as i will not be using many electronic options anymore and seeing as i will be using all new aftermarket guages.

 

aftermarket gauges tap into any wiring. they have have sources for anything your going to meter.

 

painless? yea... until you pay for it...

check out these places

http://pcmamerica.com/
http://www.currentperformance.com
http://speartech.com

 

You got that right. I guess they are called painless because your wallet gets a lot lighter and you won't have back problems from carrying too much money in it.

 

Wiring harnesses have to be one of the things that you get a LOT better at after you have done 10 or so, and I am betting the first one can be a real PITA and thats the one you get to keep in your car if you do it yourself.

 

painless harnesses are crap

remove your engine/trans harness with your motor and either set it back or sell it complete with computer.

almost always the only thing you have to integrate are the gauges. lights and stuff should be ok just by getting them power to them

just use a stock LS1 harness. no modifications

 

LS1 in an 87 TA... Your existing engine harness will come right out without too much hassle. You shouldnt have to cut anything either. Atleast I didnt. I got rid of it all... The ls1 harness has everything you need to run the motor. I also used the fuse blocks out of the LS1 car. It makes things sooooooo simple. You retain all of the factory 4th gen connectors. all you need to do really is hook the battery to the fuse blocks, and give the IGN relay in the blocks 12v switched. That 12v switched wire turns on all the other relays and systems. Hook up fuel lines. Use your existing starter wires. And turn the key. It'll run (if vats is turned off). In my opinion, albeit a humble one, is that using the 4th gen fuse blocks is the way to go.

Here is why... Your fans are already wired. Just plug them in like in the 4th gen. Your fuel pump relay is there. You have fuses for all the system components, and a bunch of spares by the time you are done. Now...its alittle more wiring to sort through, but its not too bad. Some guys have figured out how to eliminate one of th blocks all together...and just have it all combined into one of the blocks. I wish I would have done that.

Your gauges, if aftermarket, will use their own senders except for the fuel leve, tach, and speedo. Speedo goes to the VSS output of the PCM. Tach goes to the tach output of the PCM. Fuel goes to the tank sender. If you put your PCM inside like I did, these are really easy to hook up. I didnt touch any of the body harness. Except to remove whatever I didnt need...which wasnt much. All of the HVAC wiring, and lights and all that jazz stay put. There is very little wiring out in the engine bay after you gut it all... Just a couple wires from the connector at the fire wall, wiring for lights and horns, wipers, and the HVAC wires on the other side. Thats about it.

All that being said...I will tell you that I used the 4th gen fuel tank, 4th gen fans, and just about anything else I could. It just made the electrical part that much easier. Good luck and if you have any other questions post them up.

Justin

 

speartech for my 88 formula ls1 project. sent the old 88 tpi harness with the ls1 6 spd harness and they fully integrated the 2 so everything works perfectly it looks factory too couldnt ask for anything better