Types of Fuel and Octane Ratings

Petrol's octane rating is a measurement of the fuel's ability to resist engine knocking. Knock occurs when the fuel-air mix in the cylinder explodes instead of burning in a controlled way. This shockwave moves within the combustion chamber, and creates a metallic 'pinging' sound.

An octane rating is often referred to as an 'anti-knock index'. If fuel has a high octane number, it will have a higher resistance to engine knocking.


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