I really don't think it's physically possible for your friend to be making 25psi on stock turbos. Even if you unplug the wastegates they're still not gonna make that. Stock turbos lose their thermal efficiency around 17psi.
"You know, after being around (1991TT) and (mongoozTT) I am beginning to notice that most 300zx drivers are more arogant about their cars than any DSMer..." - '94 TransAm owner