When you pull into a gas station, you probably notice a sign that advertises two types of gasoline which are more expensive than regular. If you purchased a high-performance vehicle, then the manufacturer probably recommends that you use premium fuel. But, what's the difference between premium and regular gasoline? And, more importantly, is it worth paying an extra 20 cents per gallon?
What's the difference?
The main difference between regular and premium gasoline is the octane level. Generally, regular gas is octane 87, while premium gas is octane 91-93. There is also a middle-of-the-road option, often called plus, that's octane 89. In addition, many premium gases contain better additives which help keep engines clean.
So, what does octane do? Essentially, every vehicle's engine is designed to run on fuel with a certain octane level. For most vehicles that level is 87, which means you'll only need regular gas. The engines of some high-performance vehicles have been designed to use higher-octane fuel and can actually have issues when the fuel type specified in the owner's manual is not used.
Is it worth using?
If your owner's manual says to use premium gas in your vehicle, then it's best to follow those instructions. While plenty of people get away with ignoring it, it will always cost less to use higher-octane gasoline than to repair the problems that not doing so may cause. If your vehicle can hold 10 gallons of gas, then filling up with premium instead of regular will only cost an extra $2.00 to fill the tank. This rises only slightly to $3.00 at 15 gallons, $4.00 at 20 gallons, and $6.00 at 30 gallons.
In addition, if the gasoline companies are to be believed, then these higher-octane fuels with better additives will actually improve engine performance. Whether or not that's been confirmed, it's never a bad idea to use a better-quality gas in your vehicle.