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It's worth knowing how much ethanol is in 93 octane gas so you can better understand your vehicle.
87 to 93 octane gasoline always contains either 10% or 15%, dubbed E-10 or E-15, respectively, and is used in most modern-day cars you'll see on the road.
However, the corn-derived additive is also used to create flex fuel which boasts a whopping 85% ethanol for special-use equipment and vehicles.
We'll go over the several benefits of adding ethanol to gasoline, how it affects the car, and whether gas stations sell fuel without ethanol in the following sections.
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Like gasoline, ethanol is a popular fuel type in the transportation sector.
While gasoline is a fossil fuel containing hydrocarbons, ethanol is made from plants, making it a renewable resource.
Made from biomass (i.e., a range of plant materials), it contains the same chemical formula regardless of whether it was made from sugar- or starch-based feedstocks like sugar cane, corn, or wood chips and crop residue.
Not only does ethanol help battle climate change, but it also has a higher octane rating than regular gasoline, so you can use it in engines with higher performances.
That said, it has a lower energy density than gasoline — 98% ethanol has around 30% less energy per gallon than gasoline.
Therefore, you need more ethanol to travel the same distance as gasoline.

According to our blog post, you can mix regular gasoline with ethanol to achieve a higher octane rating for your flex fuel vehicle.
The ratings dictate the ethanol percentage in the gasoline.
As per the USA's guidelines from the 1970s, all grades must contain some amount of ethanol content.
Gasoline with an octane rating of 93, 92, 91, 90, 89, 88, or 87 boasts an ethanol percentage of 10% or 15%, complying with the environmental protection agency and its renewable fuel standard.
When ethanol is blended with gasoline, it forms E-10, E-15, and E-85 fuel types, perfect for a range of vehicles.
Once the corn-originating fuel was introduced into the industry in 1990, it began at 10%.
The year marked the first time gasoline included an oxygenate to reduce emissions and achieve increased octane ratings.
The E-15 version is a mix of 85% gasoline and 15% ethanol.
It made its first appearance in 2012 for use in vehicles manufactured after 2001 as many brands were already making engines that could handle the fuel type without modifications.
Finally, E-85 is a blend of a whopping 85% ethanol and 15% gasoline.
It can be used in flex-fuel vehicles that are made to work with regular gas or E-85 fuels.
Using this fuel reduces carbon dioxide emissions — the greenhouse gas primarily responsible for climate change — by up to 30% compared to 93 octane and other fuels.
However, using it in a non-flex fuel vehicle can void your warranty and cause undue engine damage.

Using ethanol-containing gasoline in your vehicle will bring these positive effects:
Despite the positives, the potential downsides to using fuel with an ethanol percentage, include:
93 octane is a premium gas with a high octane rating.
Most 93 octane gas sold at fuel stations contain some ethanol content (10% or 15%), however, some companies and states offer ethanol-free versions.
Gas with a 92 octane rating can contain 10% or 15% of ethanol content.
Any gasoline with a rating of 91 or more is known as premium gas, made for use in luxury vehicles.
A higher octane level proves trickier to ignite, preventing pre-ignition and engine knocks in high-performing cars.
Constantly using the regular gas pump to fill these cars will cause problems in the long run.
Again, you can expect to find either 10% or 15% of ethanol in gasoline with a 90 rating.
However, REC-90 is an ethanol-free version designed for marine or recreational engines that require low or less ethanol to run.
Unleaded 88 gasoline contains an ethanol content of 15%.
Companies make it by combining ethanol with 84 octane gasoline.

Most of the cars sold in the United States of America (82%) use gasoline with an octane rating of 87 rather than 93 octane premium gas.
It comes in E-10 and E-15 forms and is well-suited for low- and mid-segment SUVs, cars, and trucks.
That said, always check your owner's manual as some cars can't run on fuel type as it causes an engine knock (i.e., a loud banging sound from under the hood).
If your car does take this fuel, don't fill your tank with premium gasoline because the engines aren't manufactured for it.
Normally, the cars that don't work with this gas are premium brands, sports vehicles, cars with larger-than-average engines, and automobiles with a turbocharger.
These cars tend to require gas with a 91, 92, or 93 octane rating.
Contrary to popular belief, E-85 flex fuel isn't the same as 85 octane gas — E-85 refers to the 85% of ethanol in the gas and is not an octane rating.
Like the other regular gasoline types, 85 fuel has either 10% or 15% ethanol content.
95 octane is a gas free from ethanol, therefore containing no alcohol.
It's usually utilized in limited-use engines and seasonal equipment to ensure a minimum level of corrosion and damage to the sensitive components.
Several countries (mainly around Europe) prefer gas with less ethanol, so you'll mainly find 87 octane gas in these areas as it only contains 10% ethanol.
Ethanol is a standard addition to most premium gas brands around the United States of America, thanks to its ability to reduce knocking and improve combustion.
The majority of premium gas contains 10% ethanol; however, you will find a few brands with zero alcohol content.
As we've mentioned, you can find gas with no ethanol content, particularly the premium type.
That said, the no-ethanol gases are best saved for seasonal equipment or limited-use engines.
E-10 and E-15 variants are great for most cars you'll purchase and drive today.
Most likely, mixing 87 and 89 octane gas will not harm your car. However, your car's engine must be designed to run on less than 89 octane gas.
When you create a mixture of half 87 octane gas and half 89 octane gas, you get 88 octane gas.
If your car runs on 87 octane gas, mixing 87 and 89 gas to get 88 octane gas will not improve its performance.
Similarly, if your car requires 89 octane gas or better, mixing 87 and 89 gas will reduce its performance.
Most gas stations that sell 87, 89, and 91 octane gas have a mixer pump and a tank containing these octane gasses. This mixer pump combines two different octane grades, depending on your vehicle's needs.
The minimum octane rating of your car is usually on the manual. 87 octane gas is "regular," and 89 octane gas is "mid-grade." Contrary to the popular belief that luxury cars run on premium gas( 91 octane gas), various brands can operate under 87 and 89 octane gas. Some of these are:
Audi A3; 2.0-liter turbo four
Audi Q3; 2.0-liter turbo four
Audi TT; 2.0-liter turbo
Cadillac XT5; 3.6-liter V6
Cadillac XT6; 3.6-liter V6
Lexus ES; 2.5-liter hybrid four; 3.5-liter V6
Lexus NX; 2.5-liter four
Now you know exactly how much ethanol is in 93 octane gas — those with ratings between 87 to 93 contain at least 10% and at most 15% ethanol.
The clean air act dictated the need for all gasoline sold to contain ethanol to reduce emissions and combat pollution.
Most vehicles in the United States of America run on 87 octane gasoline, but the best type for your car will vary depending on its engine, the presence of a turbocharger, and other factors.
Although, you can find gasoline without ethanol to fill up recreational and marine vehicles.
However, E-85 gasoline contains 85% ethanol and is designed for use in a flex-fuel system.
Always check your owner's manual to find out whether you need E-10 or E-15 gas for the best driving experience.

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