Fuel octane ratings and what they mean


So What is the difference between the premium fuels?

Lets start from the beginning… Deep in the earths core.

As we all know, oil deposits are hidden inside the earth, and this oil that is extracted is known as crude oil. Once this has been taken out of the ground, it is then sent to a refinery, which takes out all the impurities, so it can be converted into something more useful such as the fuel we use in our cars.

One useful conversion of crude oil is petrol. Petrol is the most common type of automotive fuel. Extra chemicals known as ‘additives’ are mixed in with the fuel and these improve the operating characteristics, to provide better fuel economy and low exhaust emissions.

The OCTANE or RON (Research Octane Number) rating is the fuels ability to resist knock or ping. This is normally produced by abnormal or excessively rapid combustion.

A HIGH octane rating indicates the fuel will not knock or ping easily. So 98Octane fuel will resist ping better than a 91 octane fuel. As a result the higher the octane number, the more additives in the fuel, the slower the burning of petrol, the better the fuel economy.

While it my be a bigger cost at the petrol station, in the long run the costs will be a lot less in repairs from bad fuel in related components.