What benefits are achieved by using premium-grade fuel?
Here where I live, it’s some 10 cents more expensive than standard.
Does it provide better mileage? If so, have there been any studies done to show that beyond/below a certain price, it’s more cost-effective to use one fuel over the other? For example, if you did get better mileage per tank of premium, is it better to buy premium at the higher price less-often, or to refuel more often at regular price?
No. The amount of fuel needed to go a certain distance depends upon the chemical energy in the fuel, among other things, like the vehicle, the type of road, etc. High octane fuel doesn’t contain any more energy per gallon that lower octane fuel. All it does is allow you to use a higher compression in the engine than would otherwise be the case. If your engine is designed for the standard low octane fuel that’s the one to use. If it is desgned for the higher octane then use that, otherwise engine damage can result.
In view of the first answer above, there isn’t any point in doing such a study. Higher octane allows higher compression, period. If you don’t have a high compression engine there is no benefit. It doesn’t “burn cleaner,” “clean your engine better,” or anything else.
There was a thread on this not to long ago. I searched, but apparently I don’t know how to use the search very well because I couldn’t find it.
The main difference between regular and premium gasoline is the octane rating. Gasoline contains a number of different oil products, and two of them, Octane and Heptane have been used to set benchmarks(Pure Heptane would rank at 0 octane). This scale measures how well the fuel can withstand being pressurized without combusting. The more pressure a fuel can withstand, the less likely it is to combust before the piston has reached the top of its stroke. fully extending the pistons provides more power and less wear on engine parts. Therefore, 93 octane premium performs as if it were 93 percent octane(though the actual mixture varies).
BTW, this is probably the thread that David Simmons was refering to, started by yours truly.
Hence, use the lowest octane you can so long as the engine doesn’t knock or ping, which will be the octane in your owner’s manual.
Wow, you guys rock. Thanks to all who replied.
Here’s what the Car Talk guys have to say about it. In other words, if you use a higher octane gas than your engine’s rated for, you’re wasting your money.