My mate ran a T4 on a completely standard 4x4 engine with 55LB siemens and it made 430bhp @25psi IIRC. However it was quite laggy, only came on boost around 4500+ His was one of the Mike R Ball Bearing cored jobs which are supposed to reduce lag too.
In my humble opinion to make the most of a T4 you really need to be able to rev past the 7000rpm limiter which means quite a bit of engine work is required.
I you want a bit more go up the revs, simple thing to do is fit a .63 housing to your turbo or use a GT30 or T38 instead.
Originally Posted by
crumpet
wont fit,You need to find a t4 trouser section which are very rare plus your turbo damper wont fit.
.
Load of shite
Trouser section is exactly the same!