i'm doing a rebuild and just tore the block apart ('90 TII). turns out that blown oil seals wasn't the only problem, housings have a couple goudges in them. they might be usable but i'm not too sure if i'm gonna reuse them on the new build up.



Anyway i just wanted to know if it was alright to use either S4 turbo housings and/or fd housings? heard of people using these. thanks

 

people do use s4 housings, but its not a good idea, as the spark plug locations are different, also there is no place for the knock sensor



fd housings are the same as s5 except they do not have the holes for the turbo water feed.

 

then how was coolant fed to the TT setup on fds? or were they just oil cooled turbos? is there somewhere else that i can run water from?

 

Theres no benefit to the FD housings. But if you sourced a pair and want to use them, Im sure you can just drill out the passage in the housing. They are cast the same.