Does using premium GAS(91 octane in a car that recommends it) get better MPG than using regular (87 octane)?

Answer 1

My experience has been that I do tend to get a little better millage and more miles out of a tank of gas. But it's hardly discernible except in this time of high pump prices. I've also noticed my engines do seem to run smoother.

Whether it's worth the extra cost or not I'm still undecided, but both of my cars recommend it and I feel better about using it.

Good luck and take care

Answer 2

If your car recommends 91, then yes.

[This goes beyond the scope of your question, but maybe it's informative...]
However, using 93 will not get you even better mileage than using 91. A higher octane rating is necessary for higher performance engines (generally those with a higher compression ratio) in order to prevent pre-ignition of the fuel (knocking or pinging). Higher octane will generally not increase the performance of an engine designed to run on a lower-rated fuel.

That said, especially with older cars (100k or more miles), I've found that running a tank of premium gas every few months does tend to increase performance (although not necessarily gas mileage).

Answer 3

Octane does not equal power, it just makes the gasoline more difficult to ignite. On engines requiring 91, 87 octane will ignite too soon, which will cause pinging. Most cars have a knock sensor, will adjust combustion, and will run sluggishly and probably inefficiently.

So, yes, you will get more MPG with 91 octane because your engine is specifically designed to run optimally with it.

On my car the owner's manual specifically recommends 87, using 91 could get me few more miles but I won't save any money, and who knows if I'm damaging something. On some cars, the manual recommend 87, and 91 for sportier performance.

Answer 4

High-octane fuel is not any more potent that regular gas. It's main advantage over regular fuel is that it is a little harder to ignite (this is what the octane rating measures). It is generally required in cars whose engines use high compression (these are typically found in high performance cars). Using regular gas in these cars can result in predetonation (called 'ping' or 'knock'), which can result in engine damage. This means that using high-test will not help your mileage any, although some cars, like the Chrysler 300M, can take advantage of the higher octane to adjust the engine's ECM to make slightly more power, but this generally decreases mileage as opposed to helping it. Even if there were a mileage advantage to using premium fuel, it would be very slight and the gain would be offset by the higher purchase cost. If your car can use regular, do so.

Answer 5

It prevents knocks and gives you more power, so yes it does give you better MPG. I always use 93 (or well 92 since moving to Oregon where they have crap gas) Octane no matter whether or not my car is supposed to be on it.

Answer 6

The higher Octane is to prevent knocking in your engine.

Answer 7

You are going to get a lot of opinions on this one.
Here's mine.

More power with higher octane = less throttle for same power of lower octane.

So, yes. You will get better mileage.

Answer 8

yes. octane causes fuel to combust at higher temperatures, thus leaving less carbon deposits in your engine. because of this higher combustion temperature, your engine will run more efficiently with more power, thus increasing your overall mpg.