Electrical V8 Swap Wiring Questions.. Help


New Member
Apr 29, 2013
Swapping a 90 v8 into a 93 4cyl shell. I have the v8 harness from the 90 and I need to know if /where/how have to wire in a fuel pump relay and if I have to mess with the maf.
I am doing a 3g alternator conversion and using the stock 4cyl headlight/alt harness and extending it.
Also what computer do I need to run?
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I want to measure mine. It doesn't look that tall.
10 Year Member
Jul 6, 2006
I don't believe the 90 engine harness will work with the 93 body/dash harness. Easiest thing to do would be to source a 92/3 engine and maf harness. No splicing or integrating needed.


Active Member
Aug 12, 2013
Nope... The 93 was a unique one. One of the changes was the fuel pump relay moved from under the seat to near the airbox. Wiring harness in the dash is different & wiring harness in the doors is different.

I'm actually doing something similar minus the 4 cy. I have a 91 im converting over to a 93.

To use a 93 harness you have to change all the wiring over to a 93. Time consuming but its do-able. If you have the option, other years are more flexible than the 93.

Edit: Also, 93 used a different latch mechanism for the rear hatch so you need that and the catch stud as well.


Active Member
Aug 12, 2013
On the hatch I think i'm wrong. I have a 89, 91 & a 93. The 93 actuator is different but functions the same as the others. The wiring pigtails on the inside driver quarter, where it connects to the harness, are the same.

The door harnesses are different on the inside of the door where it connects to the power window switches but if you use a entire door, the connectors that connect the door to the harness on the inside by the kick panels are the same.

Honestly its safer to just use the whole thing from whatever year you want to go with.
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