to push 25 psi you could get a turbo off of an airport baggage car, they are like the size of a quarter, then you can push 25 psi easily........hahaha........but you get any descent size turbo on push 25 psi with your motor stock, BABBOOOM..........shit, you go over 10psi and baboom, read the book MAXIMUM BOOST and then come back later on...........