Mpg Vs $

[BIRD]

I started my new job. And I was experimenting with the different grades of gas. I did one week on 87 octane and got only 19 MPG and then I did one week with 92 octane and went to 22 MPG. I figure with the difference in price and not having to worry about engine problems. It is better to use the 92 octane. The route I drive is 27 miles one way and is mostly high way driving at 55 to 65 MPH.

[Disco Mike]

Yes, right thru the middle of the pineapple fields, tough drive Bird.
Take care,
Mike

[LR123]

I've been using regular for the past 20k miles...Is it Ok to just suddenly switch to premium?

[BIRD]

You can switch gas any time you want, but it might take some time to see any difference. You can also try to run some Sea Foam in the gas. That will help clean out some of the carbon deposits that are built up in your engine. As for my self, I try to run a Sea Foam every 300K it helps keep things running smooth

[Disco 1]

Octane rating tells how resistant to detonation gas is. So higher octane is more resistant. So aren't you risking early detonation using lower grade gas than is recommended? That doesn't sound good to me.

[m1964]

Originally Posted by Disco 1

Octane rating tells how resistant to detonation gas is. So higher octane is more resistant. So aren't you risking early detonation using lower grade gas than is recommended? That doesn't sound good to me.

No, the engines now controlled electronically, and the ECU would retard the ignition if it sensed detonation, which may result in reduced performance, nothing you will feel at city driving speeds. You may feel reduced pull from the stop or at high speeds...