Way back in the 2000’s e-85 fuel was proposed as a magical propellant that was going to break us from foreign dependency on oil. 

It’s an alternative fuel that was supposed to be cleaner, greener, and cheaper than gas. It had some real momentum with manufacturers like Ford and Chevrolet offering cars that could run on the stuff right off the showroom floor. 

Then it sort of just went away. Nobody asked, and no one really cared. Most people don’t even know what it is, how it works, or where they could get it even if they wanted it. 

So for your benefit, we’re going to demystify this strange and unique alternative fuel by learning what it is, how it works, what it can (can’t) do for your car, and where you could possibly acquire it should you want to.

We might receive commissions if you click on our links and sign up/make purchases. However, please know this does not impact our reviews and comparisons. We try to keep things fair and balanced to help you make the best choice for your needs. Thanks.

Table of Contents

• What Is E-85 Fuel?
• Can I put e-85 fuel in my car?
  • Consumer Flex Fuel Vehicles Available In 2020-2021
• Will E-85 Fuel Damage My Engine?
• What Are The Pros And Cons Of E-85 Fuel?
• Is E-85 Fuel Better To Use Than Regular Gas?
• E-85 fuel vs Gasoline For Performance
• Is E-85 Right For You?

What Is E-85 Fuel?

E-85 fuel is a blend of gasoline and ethanol, yes the same ethanol that’s in our favorite alcoholic drinks like wine, beer, and spirits. The 85 part represents the mixture ratio so 85% ethanol and 15% gasoline. 

Officially the blend can be any from 51% all the way up to 85%, varying by weather and location. The mixture is adjusted to ensure proper combustion in vehicles during the winter and summer months.

A lot of you might not know that even pump gasoline has some amount of ethanol in it. The gas at the pumps has up to 10% ethanol in an effort to reduce pure gasoline consumption. This is referred to as e-10.

The ethanol used in the formulation of e-85 is derived from good old corn biomass distillation. Essentially it’s made the same way you would make alcohol for consumption (grain alcohol); it’s moonshine!

The colorless liquid is then blended with the appropriate amount of gasoline for its designation before it can be distributed. After that, the e-85 is ready to be filled in your tank.

Can I put e-85 fuel in my car?

Most new cars after the year 2000 will tolerate some level of ethanol, but not all can work on a high blend like e-85. Cars that can usually be denoted as Flex-Fuel capable.

To make sure your car can handle e-85, you want to consult your user manual to make sure. If you don’t have one handy, a quick google search can tell you if your car is capable from the factory of using flex-fuel.

You can also check out the U.S. Department of Energy’s alternative fuel data center to see which vehicles are flex-fuel capable, they have an expansive list of cars from consumer to commercial.

To save you the trouble, I’ve filtered the data of consumer vehicles on sale now that are e-85 ready for you in the table below.

Consumer Flex Fuel Vehicles Available In 2020-2021

Will E-85 Fuel Damage My Engine?

If your car is designated flex-fuel capable then it most certainly will not damage your engine. Even if it isn't flex-fuel capable, most cars after the 2000s are designed to run with some level of ethanol(e10) in them, because of fueling regulations.

If you happen to run an e-85 fuel in a modern vehicle that isn't flex fuel by accident, no need to worry. Your engine should be fine, you might see a check engine light and reduced fuel economy but no major damage should occur. Run through some regular pump gas afterward and it should be back to normal.

High ethanol fuel mixtures can be a problem in older engines, pre-2000’s. These vehicles were not designed for ethanol mixtures per se and the corrosive nature of alcohol could wear away at the rubber parts, particularly fuel lines.

Ethanol is also more susceptible to picking up dirt and particles because of its nature as a solvent. Dirty fuel tanks and old engines can be damaged because it will clean its way through.

In the event of a mix-up, you should be fine, but the best practice is to use the correct fuel for your car in all cases. E-85 is a fantastic fuel, and when used in the right situation can even be more effective than pump gasoline.

What Are The Pros And Cons Of E-85 Fuel?

Is E-85 Fuel Better To Use Than Regular Gas?

One fuel isn’t particularly better than the other in this case. It all depends on your situation, your car, and what you consider better to mean.

If your car can run flex fuel then you have the choice of using it. Even if it doesn’t you can find kits that will allow you to convert your car to run it. 

Emissions are important things these days, but so is the impact on your wallet. Although e-85 is cheaper at the pump than 87, the nature of the fuel is that you will get lower fuel efficiency which can be significant. 

The mpg drop can be up to 30% in some cases. No wonder it’s a difficult sell to get people to switch.

Ethanol is less energy-dense than gasoline, providing less energy output per unit burned. That's why you have to use more of it (hence lower mpg). However, it does burn more completely leaving fewer by-products than gas (lower emissions).

It’s a draw on what fuel is better, I think that’s why most people go with pump gas because they don’t have to fill up as often. 

The clear advantage then for e-85 fuel is for performance. It has some great properties that can help high-power cars and applications.

E-85 fuel vs Gasoline For Performance

E-85 fuel is better for performance than gasoline. It has higher octane which allows for better resistance to detonation. 

In performance terms, it means you can run more ignition timing and spark without having to worry about the fuel detonating. This allows for greater tunability and more power.

Gasoline has lower latent heat evaporation than e-85. Meaning e-85 absorbs more heat when converting from liquid to vapor in the combustion cycle. 

Cooler engines with more resistance to knock is why e-85 suits boosted applications so well like JDM engines. If you're interested in learning more about what makes JDM engines great check out this article.

Turbo and supercharged cars produce a lot of heat. Reducing this allows you to run more boost and create more power.

Keep in mind your vehicle has to be tuned for e-85 and have the necessary hardware to run it. This may include bigger injectors, bigger fuel pumps, and other ancillaries. If your car is already flex fuel capable then it's ready to go make more power.

Is E-85 Right For You?

For most of us, it's probably not. The benefits really are limited to performance applications and not much else.

Sure there’s the benefit of cleaner emissions for the guilty conscious but with hybrids and EV’s there are better and more efficient ways to go.

Unless e-85 becomes cheaper than electricity somehow, this alternative fuel will probably stay on the fringes.

What do you think of e-85 fuel, does it deserve another chance?