i have a 2002 wrx with a TBE, uppipe, headers, sti injectors, walbro fuel pump, hyperflow TMIC, and the vf 34. i know 16 psi is the max (safely) that the stock turbo can handle but what about the vf34? also what about internals, fuel rails, ect?

 

I've heard people pushing 22-23 but 18-19 seems the most common.

 

I'm pushing 19.5 with mine. you need a em, fuel pump, and injectors to support it. Sorry if you put that in what you had, but just wanted to make sure you saw what else you needed.

 

about 17.5 is peak efficiency for the VF34. I made much more power with more advance and 17.5 than I did at 19.5 psi and less advance when I had the 34 in.