Ok excellent cheers guys thanks for that, will give the 36's ago for now as already have them.. Its currently running a custom 4-2-1 exhaust velocity stacks with fine mesh gauze (due to space, powerscreen engine in the wrong frame ;-) ) stage 3 jet kit bst34's, compression ratio upped to 13:1 with dialled in cams... Currently making 117 rwhp & 75ft/lbs.. Any idea on gains with 36's???