What’s the Difference between Regular and Premium Gasoline?


Have you ever thought about this while filling your car up with gas?  There are always 3 options.  Regular, Mid Grade, and Premium.  Personally, I choose the regular unleaded as the price is always the cheapest.  However, I have always wondered what the difference in the fuel types were.  I did some research and here is the information I came up with.

The majority of cars are designed to run on regular gas, and that’s what the manuals tell the owners to use. Higher-performance cars often require midgrade or premium gas because their engines are designed for higher compression (higher compression = more power), and regular gas may cause knock. If your car needs high-octane gas, the manual will say so.

Using high-octane gas in a car designed for regular accomplishes little except more rapid combustion of your money. Some refuse to believe this, claiming, for example, that premium gives the family Toyota better mileage or more power. These people are in dreamland. Others say premium is purer or contains detergents that will cleanse your engine of uncouth deposits. Likewise misguided thinking–government regulations require detergents in all grades of gasoline. (BP Amoco, I notice, asserts that its premium gasoline contains more detergents than legally required; if you think that’s worth 20 extra cents a gallon, be my guest.) Some automotive types claim that using premium in a car designed for regular will make the engine dirtier–something about deposits on the back side of the intake valves. I’ve also heard that slower-burning high-octane gas produces less power when used in ordinary cars. Believe what you like; the point is, don’t assume “premium” means “better.”

In Conclusion, even thought we think more expensive = better quality, this rule doesn’t necesarily always apply to the fuel we put into our cars.  I feel more educated.  How about you?


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