Octane rating

Standard measure of the performance of an engine or aviation fuel

An octane rating, or octane number, is a standard measure of a fuel's ability to withstand compression in an internal combustion engine without causing engine knocking. The higher the octane number, the more compression the fuel can withstand before auto-igniting. The term refers to the equivalent ratio of a blend of iso-octane and heptane that produces the same knocking characteristics.

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