New to the forum and just curious if anybody has any experience with installing an 89 engine in an 87 car? I realize the ECU and harness must be swapped but the crank angle sensor connection for the 87 is part of the harness that attaches to the battery and subsequent ignightor's where the 89 crank angle sensor connector is part of the harness that connects to the ECU. Must I replace all harnesses?

 

you just need to replace the dash annd engine harness, the cpu harness(chassis) doesn't need to be changed. If you wanted to make it real simple you keep all the 87 electronics etc and jsut swap an s4 front over and omp onto the s5 engine, then swap over you s4 injectors too.

 

you can do it a couple of ways.

1. swap to 89+ harnesses, all of them

2. use the 86-88 electronics on the 89+ motor

3. use the 89+ ecu and engine harness, and make an adaptor to go to the car harness



all 3 ways work as far as i know, ive seen all 3 on it cars



mike

 

Would this be the case if the 87 car was originally a Turbo II?

 

yup, t2 and na wiring is almost the same.



mike

 

Isn't the oil injection pump also something that would need to be addressed?

 

yes either you switch to an s4 front cover and omp or run the s5 ecu and wiring, which would control the s5 electrical omp.

 

I want to do this as well. Thinking of buying a s4 gxl and putting in a s5 motor that I can get ahold of. I want to make it simple as possible. So I could just swap the motors, change the front cover, and use the s4 electronics and ecu? Will the s4 ecu work properly with the s5 high compression rotors?

 

yes you should be fine that way s93, that is the simplest way also. Also need s4 injectors.

 

or put the 89+ connectors on the harness



mike