well we have talked to precision-works turbo and a few more to get a size and basically they all wanted cubic inch and compression and your goal for hp with my combo of 440 and 8.3 comp 88 ml is perfect anything smaller your wasting your time and money but at 88 mm 1000 hp at crank is about max depends on wich turbo you buy. i have a line on a nice precision 94 mm so i can make more wich is funny my whole goal is 9 sec car pump gas but this thing has gone out of control on the budget side way the hell over. my advice call scott brown at buyracingparts.com he will mahe you a great cam my setup was about 900.00 cam lifters and springs