Here in Australia the GT3071 and GT3076 turbo's are becoming very popular with 2 litre four cylinders. .82 housings seem to get the best response and overall power output. At 26psi on a GT3076 you will make 450-460hp very comfortably. You will get postive presssure somewhere between 2800-3000rpm and it will be all on by 3800rpm. My mates car runs a Gt3076 on a cossie and it is very impressive how it drives, its a animal.