This Procharger supercharger system is designed to increase horsepower on your Mach 1 Mustang by 60-70% at 8-10 psi of boost. At 8 psi of boost this system bolts on and has substantial power gains. For the enthusiasts that want more power and are willing to alter the current configuration of their shortblock, the ProCharger Stage II Systems at 10 psi of boost and the Tuner Kits will yield higher horsepower gains. 11 and 10 second quarter mile ET's are right around the corner.