I have 2 chips in for your P72, an XS and a Jun, I'd recommend the XS for your setup, the CTR dyno to 8200 from what I've seen, I shifted my old b16a w. CTR cams and stock valvetrain at 8400-8500 rpms DAILY, never had a problem at all, power didn.t seem to roll of until about 8500 in my car. If interested I do ecu burns for $100, chip and labor.