When you go the service station do you give any thought as to what you are about to pump into your pride and joy? More to the point, should you? You might have noticed all sorts of exciting names with higher octane ratings like Premium, Super, Ultimate, Nitro+, V-Power, Momentum, but usually it all comes down to price rather than the octane rating. Clearly an explanation would be useful.
Octane is a chemical component of petrol to ensure smoother operation, and the more there is the better an engine is supposed to perform, especially sporty and super cars. The standard rating for petrol in Britain is 95 octane, essentially the minimum standard for these cars to operate comfortably. The owner’s manual or a sticker on the inside of your petrol flap will advise you of whether your car needs to be fed with premium quality, high octane fuel, usually 98 and exceptionally 100 octane.
When it comes to diesel, these are different sorts of engines which add air to the compress the mixture and so octane ratings don't come into it all. There are added chemicals though, designed get rid of sooty deposits, increase fuel efficiency and enhance the performance of the sportier diesel models.
The choice is ultimately yours, certainly putting higher octane petrol in a normal 95 rated car won’t hurt it. There could certainly be improvements in performance. However, topping up your high performance motor with lower grade fuel than the manufacturer recommends may well cause problems. Indeed, there could be an audible ‘knocking’ sound, not what you want to hear from your Ferrari V12.
For most of us the Octane rating is irrelevant and we only need to pay attention if we’re lucky enough to own a special car, which can include a hot hatchback and performance 4×4. When in doubt contact your car makers customer services department.