08/26/2026
Why don’t Super Late Models run E85 when it’s so popular with Crate Late Models?
The short answer is octane—but that is beginning to change.
More than 20 years ago, it was common for race teams to use ethanol’s close relative, methanol. Methanol could support high-compression engines, but it required nearly twice the fuel volume of gasoline. That much fuel burn-off negatively affects the car’s handling.
Both methanol and ethanol can meet the demands of high-compression Super Late Model engines. The challenge with E85 is often the gasoline portion of the blend. When low-octane gasoline or denaturant is used, the finished fuel may not provide enough detonation resistance for these engines.
At least three major race-fuel suppliers currently offer E85 blended with 100 octane or less. Many also use E98—ethanol containing approximately 2% denaturant—rather than pure ethanol. If that denaturant and the remaining gasoline are low octane, they can further limit the finished fuel’s performance.
That’s where Custom Fuels by RMB Racing comes in.
We offer custom-blended E85 made with high-quality ethanol and high-octane race fuel. Our blends can be formulated to meet the demands of high-compression racing engines.
The benefits are substantial:
✅ Potentially as little as one-third the cost of conventional race fuel
✅ Improved cooling
✅ Far less additional fuel volume than methanol requires
✅ A blend designed for your engine’s specific needs
E85 requires more fuel volume than conventional gasoline-based race fuel, but the increase is modest compared with methanol.
The future of racing fuel is changing—and we believe E85 will be a major part of it.
Give us a call today to learn more about a blend built for your racing program.