Overview: On this episode of Engine Masters presented by AMSOIL, we test the power differences between 118-octane race gas and Rockett Brand E85 ethanol-blended fuel. There’s a lot more to just the horsepower curve, though, as we test Holley’s out-of-the-box carburetor tunes, discuss other tuning differences, and go over a long list of other considerations you should make if you’re planning a changeover to E85. While the ethanol blend can be used for a variety of different engine designs, the test here focuses on a naturally aspirated, high-compression engine making 750 horsepower. Can you drive an engine like this on the street with E85 and save money on fuel? Find out on this episode of Engine Masters, which is supported by Earl’s Vapor Guard hose (specifically made to endure ethanol fuels), Mr. Gasket, Auto Meter, Permatex, and Summit Racing.