Ok so i screwed a motor when my radiator blew out so i have to replace another one. This would be my second install of a motor into a 2nd gen. The first one i replaced was an 87 13B into an 86. Well i found myself a 90 13BB and i have noticed at least one difference in the motor from the 86. The whole rats nest is different and the wiring changed a bit. I was not able to get the wiring or rats nest so i need to put that 90 motor into an 86. Anyone with any ideas or suggestions let me know otherwise i am just going to wing it.

 

'86-'88 : series 4
'89-'91 : series 5

Reuse all of the S4 manifolds/sensors/harness, etc...Only use the S5 short block & swap the front covers and oil metering pumps (OMP). You cannot just plug in a S5 EM harness into the S4 ECU / cluster without serious rewiring.