E85 Fuel, What's it all about?
E85 is a blend between regular gasoline and ethanol, generally containing 85% ethanol and 15% gasoline. The ethanol increases the octane rating substantially over normal pump gas — up to 108. Due to higher ethanol content, E85 has a greater resistance to detonation than regular gasoline and has a cooling effect on the intake temperatures your engine.
E85 is roughly 30% less efficient than gasoline due to less btu's per gallon. Gasoline is approximately 120,000 btu's vs 85,000 for E85. Therefore, the fuel consumption is higher for vehicles running E85.
Can I use pump E85?
You can use pump E85, however pump E85 should be tested for ethanol content since it can vary substantially. You can use a range of 80%-88% Ethanol in older vehicles that have a narrowband lambda sensor. Newer vehicles (2021+ Can Am Maverick X3 and 19+ Polaris XP Turbos) have a wideband lambda sensor which allows a wider range of ethanol content - E70-E92. The U.S Department of Energy allows refineries to use 51% to 85% Ethanol in pump E85 fuels. Depending on geography and seasons in the U.S., each gas station's Ethanol ratings will vary. If you use incorrect pump E85 in your off-road vehicle your vehicle may not run correctly.
Benefits of running E85?
E85 is the perfect fuel for high-horsepower, high-compression, and high-boosted engines without breaking the bank on expensive leaded race fuels. Because E85 has less resistance to detonation, it allows for more power. It is also great for cooling your incoming air/fuel charge. When air is compressed with forced induction, it causes the air molecules to heat up (expand). The cooler the air charge, the denser it will be allowing more power to be made efficiently. Along with cooling the incoming air, E85 will reduce hotspots in the combustion chamber that can trigger pre-ignition.