Strigoi

If the car isn't tuned for race fuel there's no point in using it. Using it won't magically give you a bunch more horsepower.

SICAMG

Striogi is correct and you will just waist your money.
But... to anyone looking for race fuel you can buy it in 5 gallon drums right off ebay from Torco fuels.

RaceHorse

If your car only has a basic tune with cats, you shouldn't consider using the leaded fuels mention above. However, VP makes MS109, an oxygenated unleaded race fuel, which works great on force induced motors and is a little more user friendly for the O2s. They claim hp gains of 5% which doesn't sound like alot, but on a 650hp car getting another 30hp for adding fuel is pretty easy. My experience has proven the ECU will adapt to the fuel without a retune. The MPH is a little lower at the track using 93 oct. When you start looking for big power from fuels tuning is required as mentioned above along with all the other supporting mods. I doubt you will want to go route, since these cars can break a LOT of drivetrain parts with just simple bolt ons and sticky tires. If you want to try the fuel combine it with the coldest outside temps for your area and together you will feel the biggest gains. Adding catless downpipes and a custom cold air intake will help your car make the most power on a regular basis.