Mr C,

It is a problem when you only have 1600cc's getting the turbo to spool early, BUT what I do is simply extend the rev range.

rather than having a 3500 - 7000rpm power band like my T34 1600's have, the GT30 equipped engine simply moves the power up 4500 - 8000rpm.

Its all about the cylinder head in making power! 400bhp from a cvh is straight forward once the engine strength is sorted. I personally reckon 500bhp is easily achievable, though I don't fancy the engine lasting that long or indeed the bill the customer has to pay!!! ROFLOL