Drive up to the nearest gasoline station these days and you will see the gasoline choices that you can fill in your car’s gas tank. But among these choices, most car owners will always go for the premium gasoline since it is safer for cars.

Since years back we have noted that if you don’t know what fuel to put in your car, your engine may result in the knocking sound or more commonly know as busted engines that may need to be overhauled. This was the case if you don’t use the proper fuel for your car and that is why most people have avoided using regular unleaded gasoline. But today, if your car is manufactured above 1990, you are safe and can use these alternative unleaded fuels that cost less.

While using gasoline that carried a lower octane rating than the engine required was once a sure path to disaster, that is no longer the case. Nearly all automobiles sold in the United States since the 1990s will happily run on regular-grade 87-octane gasoline without causing engine damage, a benefit of the electronic controls that now manage all engine functions.

The octane number posted on the pump is a measure of a gasoline blend’s resistance to a condition called knocking. The knocking sound — a rattling noise made by an engine under load, familiar to drivers of older cars — is a result of out-of-control combustion, the mixture of air and fuel burning erratically. The explosion rings the metal of the engine block like a bell.

(Source) The New York Times