The shop i HIGHLY recomend is API (Advanced Preformance Industries) really great shop with very knowlegable people... they work on all kinds of cars there... i've seen them custom make a rear mount turbo kit for a camero SS... i've seen them working on mercedes, honda, nissan, twin turbo a g35, you name it they can do it........ talk to Gavin there, he's a great guy who would love to help you out.. you can contact him at (714)229-0880

with out internals i wouldn't go past 6-7 psi..... and you'll probably see gains of 80-130 hp

 

I am a GIAC dealer, they are working on software for the RS4, however it is not done yet. Keep checking their web site giacusa.com, and you will see when it comes out.