...so we hear talk that a 60mm throttle opening is only suitable to say 550bhp..correct?...Most advise above this BHP go for upto 70mm...so OK....we got a 70mm throttle and an RS500 intercooler with 70mm in and out...BUT we have a turbo thats capable of 630bhp on pump fuel..aka the GT35 .82...but this only has a 50mm outlet....so why do we need 70mm everything else to get the power...surely 50mm should see the BHP?