Does E85 give you more power?

Corn ethanol has pretty much set up the stage for endless discussions and experiments revolving around this phenomenon. The discussion in itself is timely as we try and move towards finding healthier solutions for a world with lesser harmful emissions. In that spirit, corn fuel also known as ethanol fuel is one of those many solutions under observation.

You’ve probably heard of E85 which is an ethanol fuel blend of 85% ethanol and 15% gasoline. It is currently expanding really fast as more and more fuel-flex vehicles are manufactured to accommodate these fuel blends.

What is E85 and where does it come from?

E85 as mentioned above is a fuel blend of 15% gasoline and 85% ethanol. It is a renewable source of energy produced locally and is favored by many because of its clean burning properties and performance benefits.

Ethanol can be produced from a wide range of organic materials such as corn in the U.S., sugarcane in Brazil and with new technologies materials such as agricultural waste and switchgrass are also being used for ethanol production. The starch in the corn kernel is what is used for the standard ethanol while the rest of the nutrients and proteins are saved as distillers grains used as livestock feed.

Almost all the gasoline sold in U.S. contains 10% ethanol, E10, as is a requirement by the Department of Energy.

How does it work?

E85 comes equipped with notable benefits. It burns cleaner, has amazing cooling properties and has an octane rating of 105. It generally has a lower energy content than gasoline. This means that more E85 is used to yield the same energy content as gasoline.

While this is considered a disadvantage by many, it makes up for that in its richer Stoichiometric Air Fuel Ratio of 9.8:1 compared to 14.7:1 in regular gasoline. If I’ve lost you there with all the ratio talk, stay with me, it gets easier.

AFR is basically the ratio of different masses of air and fuel particularly in a combustion engine. Therefore, Stoichiometric Air Fuel Ratio is the exact amount of air required to burn one (1) unit of fuel mass.If the ratio is lower meaning that there’s more fuel than air, then this mixture is referred to as a rich mixture.

Essentially this is what gives you a lot of power. Vice versa is also true but instead of calling it a poor mixture, it’s referred to as a lean mixture giving your more economy as it burns less. It is however, not efficient as it can cause engine wear.

So, the stoichiometric air fuel ratio of 9.8:1 is rich while 14.7:1 is lean. In gasoline, the ratio means that to burn completely 1 kg of fuel, 14.7 kg of air is needed and likewise in E85, to completely burn 1 kg of the ethanol fuel blend, 9.8 kg of air is required. This ratio is the determinant of whether your engine gets better mileage and a good life or not.

E85 contains about 30% of oxygen weight and has a higher octane rating of 105 compared to gas and has been seen to perform as well as other racing fuels with ratings of over 116. High octane racing fuel costs more than the E85, saving you up to $20 but still maintain the power you would get if you were using the racing fuels.

The 85% ethanol assurance ensures more timing while your engine is running, yielding more power. This percentage does however vary, depending on weather seasons. For example, during winter the E85 blend could contain 60-70% ethanol to aid in starting the engine in cold weathers.

Another important feature with the E85 is the higher latent heat of evaporation it has over gasoline. This means that a lot more energy is absorbed from the combustion charge as it’s going through a phase change from liquid to vapor.

e85 gasoline

This heat paired with the high octane makes E85 highly resistant to detonation or ‘knock’ which increases better performance. You get the advantage of more boost, compression and ignition advance without running the risk of ‘knock’.

As we’d mentioned earlier, due to its low energy, more fuel is required to produce the same amount of energy as gasoline. At the pump E85 is without a doubt cheaper than gasoline but due to its low energy content, it will cost you more. We suggest you consider switching up your fuel system with lager fuel pumps and injectors if you’re going to make an upgrade to E85.

The advantages of this ethanol fuel blend are appreciated for any engines that become sensitive to detonation thus why it fits perfectly with boosted engines. If you aren’t experiencing the issue of knock on gasoline it is still believed that you can still get an increase in torque and power of up to 5%.

Octane rating and modern cars

The modern car engines being manufactured are highly intelligent as they have been equipped with octane sensors in the fuel lines which are then able to communicate to the computer what kind of fuel your engine is running on.

Then computer in turn accounts for the information received by tweaking the parameters in the engine such as the timing and the turbo supercharger pressure.

A good example of cars that can self-adjust to take advantage of the higher-octane fuel, is the KoenigseggAgera Rwhich when run on 97-octane gasoline gives 927 horsepower. However, when the same is run on ethanol, this number shoots up incredibly to give 1,124 horsepower and the driver doesn’t have to do a thing. The computer automatically increases the pressure from the twin turbos. This goes to show just how far technology has come and how beneficial it is becoming in creating ease while driving.

There is a set of detonation sensors that act as the computer’s ear on the engine and they are therefore able to raise an alarm if the engine is pushing it in terms of taking advantage of the higher octane fuel i.e. ethanol.

Does E85 work in my car?

This is a concern that many people have, seeing as most of our gasoline now contains 10% ethanol. You may actually have a flex-fuel vehicle and not know it. This is because most cars manufactured after 1980 can run on fuel blends of E10 (10% ethanol and 90% gasoline) or higher. FFVs especially have been made to run on ethanol fuel blends of up to 85% ethanol.

Another way to keep your mind at ease is that by just a few modifications your car can enjoy the benefits of running your engine on E85. The aftermarket and tuning world has helped in such modifications. However, these conversions have been known to fail in terms of their efficiency in making conventional engines run on ethanol fuel blends. They could also make your warranty invalid. They are also illegal not unless certified the by the United States Environmental Protection Agency.

Some cars you probably didn’t know are FFVs

V8 Dodge Dakota

For all truck lovers out there we start of the list with the Dodge Dakota that shook up the pickup truck market a bit by becoming the first small-scale truck having a full V8 engine as well as the first medium sized truck to be sold on the market. This truck is equipped with ethanol capability which gives the user engine power and the advantage of a full-sixe truck all in one package.

2.0L Ford Focus

For a compact car that’s been in the market for quite some time now, the Ford Focus ensures that its users have the comfort of driving with the added advantage of fuel efficiency. This is because the 2.0L engine can run on E85 fuel. Added to its other great features, it is affordable to buy raising the bar high for cars such as the Corolla.

4.7L Chrysler Aspen

Even as the brand continues to struggle for identity, they still try and manufacture different vehicles that will have you walk into their showroom. Fun fact: it’s not just brands that struggle with identity crisis … we do to. Anyway, they manufactured the Chrysler Aspen which was based on the Dodge Durango but with a more luxurious feel to it. It also came with an engine compatible with E85 adding to some of the few SUVs that are fuel efficient.

Those are just a few vehicles that are compatible with E85 meaning when it comes to having more power, they are able to deliver.


Without a doubt, E85 when it comes to power, will take you where it is you want go. However, you need to be careful if you’re considering tuning your car E85.

For individuals who are constantly switching between gas and E85, it’s nearly impossible to drain out a factory fuel tank and as such the remaining fuel combined with new fuel will result in a fuel variation that could potentially be damaging. To deal with this, Andre Simon, suggests you use an ethanol content sensor. This will help your tune adjust automatically saving the trouble.

In conclusion, the question of whether or not E85 can give you more power is evident with the racing world mainly dominating in buying this fuel. However, the properties of ethanol such as moisture absorptions and low energy content, one ought to think through the pros and cons and see which of the two favors them before making the switch to E85. For more information, here’s a link to follow:


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