So going from a 91 motor into a 88 car is a pain in my you know what. So my next question comes from the metering oil pumps being different. I took my front cove from the 88 and put it on my 91 motor so that i can run the mechanical metering pump off the 88 where as the 91 is electronically controlled. I am using the 91 intake with the set up to run the 88 pump... Woo Hoo... So please give me some insight on the situation. If not i will let you know how it works out... LOL... I might be looking for a motor this weekend... Hope not... Have a good one.

 

You will need to use the S4 throttle body and S4 electronics (TPS, ECU, pressure sensor, AFM...). The S4 TB has the mounting location for the OMP rod.

You will need to:

1) Bend the rod to fit around the wider S5 intake manifold
2) Grind down a spot on the bottom of the S4 TB so it'll clear the S5 UIM
3) Spin one of the S5 TB mounting studs out a little ways to properly accept the S4 TB.

You're essentially doing part of the modifications needed to use an S5 intake manifold set on an S4 block. Here's a writeup on that: http://homepage.mac.com/carldavis/intake.html. Pictures of the modification areas I listed are included.