Our Stage 4 (previously stage 3) upgrade was developed for our customers who want to run 10 second quarter mile times and beyond supercar levels of performance!

The Stage 4 power upgrade for the ISF Supercharger kit achieves 650whp to 714whp on e85 fuel (about 760hp to 860 at the crank @ e85 content of 70-80%). Internally stock ISF engines are recommended to run 50% e85 blend or higher for maximum safety/reliability.

Stage 4 upgrade kit includes:

• Innovate Motorsports e85 gauge
• Upgraded port fuel injectors
• Fuel surge tank with integrated fuel pressure regulator
• Radium surge tank with TI Automotive fuel pump
• All fittings required for fuel system installation
• Teflon lined braided fuel hose
• Revised ECU tune as well as base maps for external fuel computer for pump gas, e50 blend, and e85.
• Upgraded port fuel injectors (necessary for power levels over 600 whp)






Please note that running on regular high-octane fuel will require switching the tune file. Running on regular high-octane fuel without 55% ethanol is not recommended at full throttle.