im looking to do around 20 lbs of boost which turbo for an s5 would do that and what else would i need

 

read up on how turbos work or speak to a turbo specialist, boost pressure is relative to CFM ratings: a stock turbo putting out 20 PSI is doing a whole lot of nothing but a big T66 putting out 20 PSI is doing a hell of a lot more and then there is the intercooler factor but we won't go into that right now...

 

well im looking at thwe stage 4 turbo on rx7store.net and i was wondering if it would be normal to get around 17-20 on that

 

Not recommended.

Do your research first.
Being a boost junkie will usually end up killing your engine.


-Ted

 

Also best to have the motor rebulit at the same time your upgrading a turbo. Find out what kind of parts you need to up grade to be able to run 20lbs with out the engine starving for fuel or oil.