E85 vs. race gas dyno

As race car enthusiasts and drivers, there are many reasons why race car fans and drivers are confused between e85 and race gas dyno. Whether it is because of the prices, better engine performance or simply, for the conservation of the environment, the list is endless. However, more professional race car drivers are choosing to use high octane rating fuel.

In 2011, American Ethanol and NASCAR partnered up to promote the use of their E15 gas. The 98 octane fuel blend was used in three of NASCAR’s national series; whereby NASCAR achieved 7 million miles of racing using the mixture by March 2015. So, why are more and more race car drivers using high octane rating gas?

E85 vs. commercial race gas

E85 gas is a highly oxygenated fuel comprising 85% ethanol and 15% gasoline, depending on the geography and climate. It is a renewable source of energy that is domestically produced from a wide range of organic materials such as corn, agricultural waste, wood chips, and switchgrass. This alternative fuel burns cleanly with better engine performance on a race car and reduced tailpipe emissions.

oxygenated fuel

Many motorsports enthusiasts overlook the benefits of e85 gas because the gas is often associated with low-performance flex-fuel vehicles. However, on an adequately boosted vehicle, you get increased horsepower with every dollar as well as improved street ability.

Commercial race gases are usually highly oxygenated unleaded fuels with a high level of octane. They contain several additives to increase shelf life and promote cleanliness in the engine of a vehicle. For optimum shelf life, it is advisable to store such gasoline in opaque and tightly sealed containers, and under room temperature.

Race gas is best for off-road use and in racing cars due to their highly oxygenated nature. Typically, they have about 20% of ethanol, which increases the overall octane level of the gas. However, your vehicle will require an increased fuel flow to ensure the engine is running at its best performance.

Does race gas make more power than E85 gas?

race gas

Race gas has high octane rating level that is ideal for racing cars. It provides excellent resistance to detonation in their internal combustion engines. The higher the octane rating, the more the boost/ or timing run on a racing vehicle. Race gas adds power to any engine, unlike E85 gas, which is only suitable for flex-fuel cars.

Race gas is more expensive than pump gas as it ultimately gives more power that is ideal for the track. However, what about when your racing vehicle is no longer on the racing track? Is it worth the extra dollars to buy race gas? Luckily, there is a pump gas that provides high-octane levels and costs even less than regular gas; E85 gas.

E85 gas has 85% ethanol and 15% gasoline, meaning car owners will have to substantially tune their engines to fit the varying blends of E85 gas. According to the US governing body (regulation ASTM 5798), ethanol content in E85 gas can vary from as low as 51% to 83%.

Despite E85 low costs, consumers have to use a substantially increased amount of the gas to reach the same fuel/air mixture needed for complete combustion as compared to standard race gas. As a result, there is a reduction in fuel mileage, and it can also destroy fuel systems not designed for ethanol-based fuels.

Why do cars make more power on E85?

E85 vs. 91

E85 gas supplies racing fuel properties at discounted prices. However, you have to tune your engine and fuel system to protect them from the corrosive nature of ethanol. Its high octane rating and cooling properties contribute to how the gas makes more power.

Octane rating refers to the fuel’s ability to prevent knocking or detonation. With too much ignition or boost, the engine of a vehicle can detonate; thus, octane rating limits the power/boost made. E85 gas has a high octane rating, and when combined with its cooling properties, the detonating resistance of this gas is much higher than the actual octane rating reading would suggest.

E85 gas has a high latent heat of evaporation. When this gas finds its way into your vehicle’s engine, its ability to quickly change from liquid to gas, releasing heat from the intake charge, allows the gas to produce more power; hence, making the engine less prone to knocking.


When it comes to E85 vs. race gas dyno, E85 gas makes more power than race gas. However, there are several factors you have to consider before switching from regular race gas to E85 gas. E85 pump gas is different from brand E85 gas as these fuels may have varying octane ratings from one fuel station to the next. Each ethanol percentage has different tuning requirements; otherwise, it can bring potentially dangerous results to your fuel injectors as well as your engine.


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