Also I wouldn't have thought a zd30 would be that much higher than 350- 450 maybe. if a non turbo 2ltr 4cylinder uses around 141 cfm at 4000rpm (from the little reading I've done) I know at 15 psi would be compressing the air a bit but I've not looked at how dense it gets to work out the real volume but it can't be that much more.