Higher Octane Gas IS Better - If You Can ACTUALLY Get It, amirite?

Though true, he is getting better mpg because he is buying non ethanol race fuel at that one gas station. Ethanol has less energy density.

by Anonymous 4 days ago

This is entirely engine dependant, no?

by jalonhuel 4 days ago

Yes. High-performance cars like sportscars need to be fueled with 98 octane. Normal cars won't see a difference, they'll be burning just as much of 98 as they would have of 95

by Anonymous 4 days ago

Higher octane gas doesn't give better fuel mileage. Its only purpose is to prevent premature ignition in engines with higher cylinder pressures, be it from forced induction or simply a high compression ratio. .

by Anonymous 4 days ago

This is why you pump your own gas....

by Anonymous 4 days ago

It keeps low performing people to have a job

by Anonymous 4 days ago

It's a popular fact. Car manufacuters once asked the US Government to mandate that all gas be premium as it would allow them to hit emission targets easier. However, having multiple grades of fuel allows oil companies to extract more profit.

by Downtown_Beat 4 days ago

And higher compression ratios have no effect on knock? You could advance timing beyond the standard, which would also increase efficiency. Of course they have more variables to change at the design stage. Anything with a turbo can be tuned (or even be able to detect like some Mazda engines) for higher octane and run more efficiently. That might be the case for OP.

by Downtown_Beat 4 days ago

It does. But it's the compression making the motor more efficient not the octane. E85 is 115octane but ethanol has less energy density. Thus you get worse fuel mileage Op is getting better fuel mileage because he is purchasing non ethanol race fuel. Again not because of the octane.

by Anonymous 4 days ago

Yeah, OP is using Shark Attack = Ice Cream sales logic here.

by georgiana26 4 days ago

This is just factually wrong. If the engine doesnt call for higher octane, than you'll see no benefit. The man filling your tank must be referring to cars that need high octane, so it doesn't denote prematurely causing you to not feel "shaking" and run "smooth".

by Anonymous 4 days ago

My guess is OPs two trips where they saw differences in MPGs are two totally different driving conditions. Probably a highway driving trip to get the 30 and a city driving trip to get the 25.

by Moist_Watch4168 4 days ago

Sure if your car is design for high octane gas you should use it. If your car is not designed for high octane gas then using it won't help and you're just throwing money away.

by Chance-Ad-3916 4 days ago

In North America octane is calculated differently, so our 87 would be around 92 in Europe, and our 93 would be around 97.

by Sensitive_Prize 4 days ago

"Bigger number=better" energy. Wait until your engine starts knocking.

by Anonymous 4 days ago

Try 100 octane avgas sometimes.

by Overall-Translator63 4 days ago

I forgot about that. We used it before the useless catalytic converters where required.

by Overall-Translator63 4 days ago

Octane has nothing to do to efficiently. Octane is just the measurement that refers to it resistance the pre ignition. If you are actually getting better gas mileage due to using higher octane it because one of two things. You car requires it. Or its becasue your car is running poorly due to something like carbon deposits. If needed I can go into alittle more detail.

by Lumpy_Bottle_5843 4 days ago

The higher octane gas you are getting is ethanol free. Ethanol is less energy dense than gasoline by about 20%. Standard gas is roughly 10% ethanol. Octane has nothing to do with it.

by Anonymous 4 days ago

2014 Kia Forte will not get any better miles per gallon on 87 vs 93. You would be paying for nothing.

by Aggravating_Jump_327 4 days ago

Sometimes I wonder what the hell people think when they see the words "unpopular opinion" Nobody thinks that lower octane gas is better than higher octane gas - it's just a question of whether the higher price is worth it, and that's entirely dependent on your car's engine and how it's tuned.

by Dangerous_Bike_4459 4 days ago

Higher octane only matters if your engine requires it. Using 93 octane fuel in a car that's designed to use 87 will not yield you better mileage. If your car takes 87, then you're wasting money by putting higher octane fuel in your tank.

by Moist_Watch4168 4 days ago

High octane gas only matters if the engine is designed to use it. Using 93 octane in an engine designed for 87 octane gets you nothing.

by Any_Ice8596 4 days ago