What am i getting into if i mismatched s4 housings with s5 plates??? 88 gtu housings are original to my car. The s5s are out of an 89 god knows what ... But they are mint . Is this a problematic combo!?

 

I think that the only diference between s4 and s5 engines is the rotors,electronics, and possibly the irons but you should be able to do it and when you say plates do you mean the irons and I think the spark plug timing is different on the rotor housings so you shouldn't use 1 s5 rotor housing with 1 s4 rotor housing

 

You can swap housings, just make sure that each housing matches the series of the other.

ie, don't use one S5 and one S4 housing.

 

im wanting to keep all of my s4 stuff and just replace s4 irons with s5 irons. with out changing anything else at all?

 

you should have no problem doing that at all from what i have seen in videos and of my own experience of tearing my s5 n/a engine apart. the irons are pretty much the same from what i can see, i just dont know if the auxiliary ports and intake runners are different but you can tell when you are switching them out if you are doing it yourself that is.