Well I've heard the swap is pretty direct (S5 motor/trans into an S4 car)

The only problem I'm expecting to encounter is with the oil metering pump, since the S4 has a mechnical OMP and the S5 is electronic. I have a whole donor car so I COULD swap everything including the wiring harness, but that's alot of work.

Has anyone done this before? Any solutions to this problem would be great. Thanks.

 

if you do the s5 into s4 swap you have to change the front cover so you can use your mechanical oil metering system, unless you want to do the whole s5 swap with ecu and all rotaryresurrection.com has a right up on this

 

yes alot of peole have done it
and a search will bring it up