While E85 is typically cheaper per gallon than gasoline it might be more expensive per mile. Since ethanol contains less energy per volume than gasoline, FFVs will generally get 15%-27% fewer miles per gallon when fueled with E85, depending on the car and the driver's driving habits.
The Disadvantages to using E85.
The main disadvantage to using E85 is the fact that it's less dense than traditional gasoline. This means that your car will need to burn more fuel to get the same amount of distance compared to petrol, this works out to be about a 30% increase in fuel consumption.
E85 does get less mileage than regular gas, however, it's a matter of crunching the numbers, according to De Haan. He said if E85 is at a 20% discount or greater compared to gasoline, it may be worth it. The fuel can also run in short supply, and sometimes gas stations can have the pump shut off.
E85 Cools Your Engine Better Than Regular Gasoline
Ethanol burns cooler than regular gasoline. It requires lower combustion temperatures. Also, it creates a thermodynamic cooling effect that regular gasoline doesn't offer. This is quite beneficial because E85 helps keep the engine cool.
E85 fuel has a faster ignition time and flame propagation when compared to gasoline. This leads to higher cylinder pressure, as well as increased engine torque and power, gaining up to 20%.
E85 is such an effective cleaner that some people run about 1 or 2 tanks worth of E85 through their engines instead of using a fuel injector cleaner. A surefire way to ensure that your engine remains clean is to use E85 often (or all the time).
Ethanol also has a higher thermal efficiency meaning when it does ignite, the temperature of the combustion is lower compared to pump gas. This allows a turbocharged engine to take more boost within a safe operating range without damaging the engine.
E85 has an octane rating higher than that of regular gasoline's typical rating of 87, or premium gasoline's 91-93. This allows it to be used in higher-compression engines, which tend to produce more power per unit of displacement than their gasoline counterparts.
It's also often called 'Flex Fuel'. As the name suggests it's 85% ethanol and only 15% regular petrol, meaning that in addition to having better performance characteristics, E85 could have a slightly lower impact on the environment while supporting local industry.
Flex fuel that contains a higher ethanol content won't last as long as flex fuel that contains a lower ethanol content. For example, E85 contains 85% ethanol, and E20 contains 20% ethanol. That means E85 won't last as long as E20. The good news is if E85 evaporates and/or absorbs moisture, it doesn't happen right away.
Ethanol has a corrosive action on fuel-system components, magnesium, aluminium and rubber. Running E85 on older model engines without tuning and replacing some components will ruin the engine in short time. Replacing fuel hoses, fuel pumps, gaskets, seals, fuel filters, fuel injectors, throttle bodies, etc.
The drop in fuel economy is because ethanol has lower energy content per gallon than gasoline. E85 also burns faster than regular gasoline because it vaporizes faster. So your engine may eat through E85 faster than regular gasoline.
Engines with higher compression ratios and materials that are sensitive to corrosion may experience increased wear and tear if operated on E85 exclusively. Mechanical parts such as fuel pumps, fuel injectors and pistons may be at risk of damage from the higher water content of E85.
E85 has higher octane than regular gasoline. This means that E85 is a lot better for your car's engine than regular gasoline. It is also a cleaner fuel with lesser harmful emissions. On the downside, E85 burns faster and produces lesser energy than gasoline.
If your car isn't a flex-fuel vehicle and you mistakenly add E85 to your tank, you may notice reduced performance and gas mileage. Your check engine light may also appear, but the mishap likely won't damage the engine. They recommend topping the tank off with regular gasoline several times.
What is the octane rating of E85 compared to gasoline? E85 has an octane rating ranging from 100-105, making it a high performance fuel. In comparison, regular unleaded gasoline has an octane rating of 87.
E85 gas is suitable for use in any vehicle designated as a flex-fuel vehicle by the manufacturer. Cars.com reports that flex-fuel vehicles are capable of running on both ethanol-gasoline blends and regular gasoline.
The octane of E85 is about 100 vs 87 for normal fuel. For E85, you can expect a few percent more horsepower and about 30% less fuel economy.
Because of E85s increased resistance to detonation, it allows for more power without the cost of expensive race fuels. Even at low power levels, E85 can also be a much safer fuel than normal pump gas. Much like methanol injection, the alcohol present in E85 is great for cooling down your incoming air/fuel charge.
Simply put, if you mix 5 gallons of 91 octane pump gas with 5 gallons of E85, you get 10 gallons of a 96-octane fuel that's very close to E50, or 50-percent ethanol and 50-percent gasoline.
Using any octane level of gasoline in a flex-fuel vehicle is acceptable. The sensors in an FFV detect whether the fuel is pure gasoline or 85% ethanol and make necessary changes for optimal fuel injection and timing of combustion. Putting E85 in a car not designed for flexible fuel can be harmful.
What Are the Positives? E85 fuel can give you a significant boost in power and torque without breaking the bank for racing fuels. It has a base octane rating of 105 and has the bonus of added cooling properties that add even more knock resistance than racing fuels with the same rating.
Your car will also run better because the ethanol in E85 is a solvent that can clean the carbon deposits throughout your engine and fuel system, and the high octanes enable the engine to produce more power.
It's necessary to have such large injectors when using E85, because you must plan for about 30 percent more fuel, due to E85's lower energy.