Originally Posted by Matt J

Why dont people look into things better before claiming shit like that? lad currently has said turbo and around 340bhp, took the head off to freshen it up and his "tuner" has told him to swap the cams and slight headwork and he'll get 430-450bhp on the same turbo

I'm no cossie expert but I thought a .63 T35 running 30+psi would just scrape 400 but thats wringing its neck and probably wont last long.

What boost would be needed for 450 on a T4? early to mid 20's? and whats the best he can expect for that boost on that turbo?