hawgranch

I've got an 85 IROC and I'm currently swapping a motor out of an 88 IROC into the car.My question is,can I just swap the motor and tranny with the 88 wiring harness,or will I have to swap all wiring in the car to do the conversion?The 85 had a 305tpi,with an auto,and the 88 had a T5.I've already noticed a huge difference with the components in the two cars,and any help or suggestions would be greatly appriciated.

bigmike87

pull the motor out of the 88 with the harness attached ( disconnect the harness from the block behind your brake booster and unplug harness from ECM behind the dash on the passenger side and snake it through the side of the firewall and out. your gonna have to take off the passenger side fender. Now assuming you have the whole 88 iroc car pull out the entire dash harness and all and swap it over ( dont worry not very hard at all) if you dont have the whole car try and score a dash and harness out of a 88 TPI wreck. when you remove the dash and harness out of your 85 cut the section that runs to the *** end of the car for tail lights, ect. and when you put the new one in just splice it to the existing wires, there all the same colour regardless. saves you the hassel of trying to pull all the tail light wires through. and hook it all up use your ECM out of the 88 and she should fire right up. if your 85 was not a TPI car you will need the fuel pump and lines from a TPI because they run higher fuel pressure ( its easier just to swap tanks. hope this sheds some light on the situation.

bigmike87

o and all the wires that run to the steering column should be the same. I dont believe GM introduced the VATS sytem ( Vehicle Anti Thef System ) until 89 so there should be no problem there. just take your time. its not that bad.