Gas Octanes Explained

When you fill your gas tank in Omaha, you’ll notice three main grades of unleaded fuel at the pump. There are Regular, Midgrade, and Premium fuels. The main differences among these three types come down to gas octanes. You might notice in your owner’s manual that the manufacturer recommends a regular gas octane. However, if you own a high-performance vehicle or one with a turbocharged engine, you might need a premium gas octane instead.

Read our guide to gas octanes explained by the team at Sid Dillon near Fremont. 

Gas Octanes Explained: Minimum Octane Rating

When looking over your choices for gas octanes, you’ll see the big yellow numbers on the gas pump. Regular gas octane typically says 87. Mid-grade gas octane usually says 89. Meanwhile, premium gas octane normally says 93. 

This label is the minimum octane rating, which is derived from two numbers. A machine tests the fuel in laboratory conditions, giving an octane number of an idling engine and an engine under higher speeds. The numbers of the test are compared to the known numbers of other fuel types, like toluene, heptane, or iso-octane. 

Then, the two numbers are combined and divided by two to get the (R+M)/2 figures for gas octanes you see on the gasoline pump. 

Gas Octanes Explained: Differences Between the Numbers

The gas octanes you see measure the stability of the fuel in your engine. Regular gas octane and premium gas octane come from the same basic refined unleaded gasoline. The main difference among these gas octanes is that the ratings are based on the pressure at which a fuel spontaneously combusts.

The higher the octane level, the more stable and more predictable the gasoline will combust under pressure. Gasoline with a higher octane rating has less of a chance of causing engine knocking, which can damage your new vehicle. Also called pre-ignition, this occurrence is less common with premium gasoline.

Gas Octanes & Engine Suitability

Fuel with a regular gas octane rating will burn faster than one with a premium gas octane rating. Regular gasoline works better in engines with lower compression ratios. High-compression engines will benefit from and probably require premium gasoline for optimal results. 

Gas Octanes & Price 

Premium gasoline can cost 20 to 40 cents more per gallon than regular gas. Those fuel costs add up over time on drives through Lincoln, so it’s important to know the differences when selecting your gasoline.

Pro Tips for Choosing the Right Gas Octanes

When choosing regular or premium gasoline, look over these tips: 

• If your car does not require premium gas as stated in the owner’s manual, premium won’t boost the performance or the longevity of the engine.
• If your vehicle requires premium gas, using regular gas usually does not harm the engine. If you hear knocking when you use regular gas, switch back to premium gasoline. 

• Turbocharged engines almost always require premium gas because they burn high-octane gasoline more efficiently in these higher-pressure environments.
• It’s best to follow your owner’s manual for the right octane level of gasoline

Gas Octanes Explained at Sid Dillon

Do you have more questions about how gas octanes work? Contact us or call , and we’d be happy to help. Does your car need service? Look over our service specials to see how much money you could save and then schedule service with our team.