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If you drive up to a typical gas pump in the United States, you will have anywhere from two to five options when it comes to the kind of gasoline you can pump. The differences in the gasoline types is based on the octane rating of the fuel. Octane measures the performance of engine fuels. This measurement indicates how much compression must be applied to a fuel before it spontaneously ignites. The higher the rating, the higher the compression level. This rating is important when it comes to engine performance.

Why is octane important?

Cars that run on gasoline use internal combustion engines. These engines use spark plugs to ignite a gasoline and air mixture. This miniature explosion causes the pistons in the engine to move outward and this turns the crankshaft. Turning the crankshaft transmits power through the transmission to the wheels.

One of the biggest issues found in the early days of gas-powered vehicles was knocking in the engines. Knocking occurs when the gasoline and air mixture ignites prematurely, making the piston bang against the engine headers. This premature ignition happens because the compression within the engine is high enough to ignite the gasoline without the spark plug.

Fuels with a higher rating have less chance of causing engine knocking. In high performance engines, that use high compression levels within the engine, the need for high octane fuel is critical.

What do the octane numbers mean?

The lowest octane rating sold in most U.S. markets is 87. The highest is usually 91. Other ratings available include 88, 89, and 90. What do all these numbers really mean?

If you look at a gallon of gasoline at the molecular level, you will see chains of carbon and hydrogen atoms. These hydrocarbon chains come in various lengths. If there are seven carbon molecules in the chain, it is called a heptide. If there are eight carbon molecules in the chain, it is called an octane.

Heptide molecules ignite readily under compression and octane molecules do not. The more octane molecules in a gallon of gas, the less likely it is to ignite under compression.

The octane number relates to the percentage of these molecules in a gallon of gasoline. If a gallon of gasoline has an 87 octane rating, that means it has 87 percent octane molecules and 13 percent heptide molecules. A 91 octane rating means 91 percent octane and 9 percent heptide.

Many vehicle manufacturers recommend the gasoline octane rating to use in a particular vehicle. High performance sports and luxury cars often have the need for higher octane fuels to maintain peak performance. It is important for consumers to refer to manufacturer recommendations before purchasing gasoline for their vehicles.

Fuel retailers often sell two or three kinds of gasoline to consumers. Understanding what the various octane ratings are is an important part of being a fuel retailer.

If you need wholesale fuel, or fuel-related services, contact us here at Kendrick Oil at (800) 299-3991. You can check out our website for complete information on our products and services. You can also read more about the company. Feel free to Contact Us via email with any questions or comments you have.