Anyway, supercharger(root or centrifugal) will make way more heat than a turbocharger at > 10 psi (according to Corky Bell). He must be doing one heck of a good job not getting detonation at that boost level. (mustang has relatively high compression ratio). He musta have atleast 400+ RWHP at that boost level, good to hear that you can pull him away at stage 4. Good Kill anyway.