I am a dealer for these, used a few 76mm ones on gen 3 setups, worked a treat, std ls1, 76mm roller, 10psi 460rwkw mainline dyno, another one I did 76mm ls2 std 14psi 580rwkw mainline dyno, and backed it up 147mph vy ute id recommend them to anyone and everyone, im going to put a billet wheel 70mm on my own xr6 soon