Grade of Gas helped

[Aveo5_boy]

Overdrive:

Do you believe that octane has an effect on the MPGs? Really?

Aveo5boy:

Do you believe that octane cleans the fuel system? Really?

Octane rating is the gasoline's resistance to self combustion, thats it. higher octane means more resistance. when gas ignites through self combustion, it is called pre-ignition, or knock.

Higher compression pistons will require more resistance to self combustion, hence a higher octane gas needed.

If 89 octane gave 5 more MPGs, they would recommend 89 from the factory and selll the higher mileage. Could have been a number of things that increased your mileage, but it wasn't 2 octane points.

Additives in the more expensive grade may help "clean" the fuel system, but it is NOT the octane cleaning the system.

I am shocked that you guys are on the internet but don't just google this stuff.
A lot of mis-information here.

Maybe one of the repected members here can confirm this. I bet petrified rabbit knows the deal.

AveoJunk:

Take the time to read what I posted again.......When I said higher octane fuels I was refering to the highest grade of gas like supreme, premium, super whatever you want to call the most expensive gas at the pumps & not what octane alone can do. Sorry for the confusion if it came across as sounding like octane alone.

Also it seems you have never tested a full tank of higher octane fuels in your car which I have many times recording mileage as well and "yes" it does give you more mileage than the regular 87 fuel but not enough to justify the difference in cost. 91 fuels contains no ethanol thus the reason for extra miles and the reason why flex fuels give you less mileage....pretty simple to understand. Next time you should do your own personal tests first then give your comments on the matter! Thanks