Maybe, but only maybe. Much publicity about this fuel has been confusing and perhaps misleading. Here are straight facts: The significant difference between petrol grades is in octane rating, which tells you nothing about a fuel except its antiknock quality. Buying more octane than your car needs is wasteful. It will not necessarily (1) give more power, (2) provide greater mileage, (3) make your car easier to start, or (4) supply widely-claimed benefits that will increase the life of your car’s engine.
There are some misconceptions about octane rating. Actually, it’s a technical term with a number and it seems to be a yardstick that measures general quality of fuel. The numbers sound like grades on an examination paper — and everybody knows that 95 is better than 90 and 100 is better than either. But when it comes to octane, that view is deceptive. For the car owner, suiting an engine’s need is the real criterion as to whether higher-octane petrol is better or not. The fact is that one would not find consistent differences between ordinary and premium fuels, other than antiknock behavior. The knock or thud you hear from the engine is a sure indication that the fuel is not burning properly. During normal combustion, fuel-air mixture is ignited only by timed spark. But sometimes unburned gases get hot enough to start another fire either before or after timed spark which results in multiple explosions and causes knock that is irregular and recurrent. These explosions means trouble–repeated jerks, loss of power, over-stressing of engine parts and possible damage. But if the lower-priced ordinary fuel doesn’t cause knocking, there is no point in feeding your car premium fuel.