Premium Gas = Higher Gas Milage??

[tonystewart]

That's great advice, been following this philosophy for years

[SuperchargedMR2]

The problem with using premium gas in engines that don't need the higher octane is that it can cause higher carbon deposits. I've tested premium in every car I have had for the past 30 years & I've never seen any mpg benefits in any of my cars. I also have always keep a mileage log for every car. Changing your bad driving habits will have a bigger impact on mpg than using premium.

[noahthefrog]

I've never measured a consistent difference in mpg between regular and premium on any car I've owned, except when driving in places where they add ethanol to regular but not to premium. Ethanol produces less power per gallon so it takes more gas to do the same work (ie travel a mile). Gas that has ethanol blended in is probably the reason for a lot of the observations of higher gas mileage with premium.

If a car is designed for premium, then you can expect it to be most efficient on premium. Otherwise the better/extra additives or lack of ethanol are the only benefits to using a higher grade of gas. Mid grade is a mix of premium and regular - 1/2 and 1/2 mix if the station sells 91 octane premium. I notice an improvement in performance and idle smoothness with 89 octane but no difference with higher octane, so that's what I use. I seriously doubt the octane is the reason it runs better on mid-grade since my engine calls for 87 octane and has 20 years of wear on whatever compression it started with... I credit the additives for the improvement.

[Bitter]

its all in your mind, you pay more for the gas so you drive it more gently. mwahahaha

[BlackG5]

Originally Posted by SuperchargedMR2

Changing your bad driving habits will have a bigger impact on mpg than using premium.

^this.

Originally Posted by Bitter

its all in your mind, you pay more for the gas so you drive it more gently. mwahahaha

^and this..


you're wasting money by using 93 because let's face it, unless you're heavily modded, you drive an economy car that was designed to run on the cheap stuff.