The Benefits of E85 in High-Performance Cars

When it comes to squeezing every ounce of power from a high-performance engine, fuel choice is just as important as the mechanical components under the hood. One option that’s been gaining popularity in the performance world is E85—a blend of 85% ethanol and 15% gasoline. Originally developed as an alternative fuel, E85 has proven itself to be a game-changer for racers, tuners, and enthusiasts looking for more power, better cooling, and even cost savings.

1. Higher Octane Rating = More Power

E85 typically carries an octane rating between 105–108, far higher than premium pump gas (91–93 octane). Higher octane means the fuel can withstand more compression and timing advance before detonation occurs. For turbocharged, supercharged, or high-compression naturally aspirated engines, this is a huge advantage. More boost and more timing directly translate to more horsepower.

2. Cooler Combustion Temperatures

Ethanol absorbs more heat during combustion compared to gasoline. This cooling effect helps lower intake air temperatures and combustion chamber temps. Cooler air is denser air, allowing more oxygen into the cylinder—and with proper tuning, this means more efficient combustion and more power. It also helps reduce the risk of knock, giving tuners more headroom.

3. Increased Oxygen Content in Fuel

E85 contains oxygen molecules within the ethanol itself. This “built-in oxygen” allows engines to burn more fuel efficiently, supporting higher power levels. In practice, many cars tuned for E85 see gains of 20–30% more horsepower compared to pump gas, depending on setup.

4. Cost-Effective Performance

While fuel economy often drops (since E85 requires more volume to produce the same energy as gasoline), the lower cost per gallon compared to race gas makes it very attractive. Instead of spending $10–$15 per gallon on specialty race fuel, drivers can often find E85 at the pump for $2–$3 a gallon, depending on region.

5. Cleaner-Burning Fuel

Ethanol burns cleaner than pure gasoline, producing fewer harmful emissions and carbon deposits. This can help reduce long-term engine wear from carbon buildup on valves and pistons. For enthusiasts who regularly push their engines to the limit, a cleaner burn means better reliability and less maintenance over time.

6. Widely Available for Enthusiasts

E85 stations are becoming more common across the U.S., especially in areas with strong motorsports or agricultural ties. With flex-fuel systems and aftermarket conversion kits, it’s easier than ever to run E85 legally and safely.

Things to Keep in Mind

Running E85 isn’t as simple as filling up and driving away. Because ethanol requires about 30% more fuel than gasoline to achieve the same energy output, fuel system upgrades are often necessary. Larger injectors, higher-capacity fuel pumps, and a proper ECU tune are essential to maximize the benefits. Additionally, fuel quality can vary at the pump, so many high-performance drivers test their E85 content before racing or tuning.

Final Thoughts

For high-performance enthusiasts chasing horsepower, E85 is more than just an alternative fuel—it’s a performance enhancer. With its high octane rating, cooling properties, and oxygen-rich composition, it unlocks tuning potential that pump gas simply can’t match. Pair it with the right fuel system upgrades and tuning, and you’ll have a potent, cost-effective alternative to race gas that delivers real results on the street and the track.