Topic: MPG on E85, 89 @10% and 87

[dg3094]

Anyone know about MPG on various gas mixtures?  I have heard that 87 octaine gives the best mpg.  I have experienced a 1-2 less MPG on 89 with 10% ethenol than 87.  I haven't used E85 yet and figured it needed to be about 70 cents cheaper than 87 to make it worth it.  Someone told me 89 had to be 30 cents cheaper than 87 octane.  Has anyone already experimented with MPG on this issue?

[bluedevil]

I cant answer this one as my AV is supercharged.  My MPG is very low

...but im sure other will chime in on this soon.

I think Sunburst05 and Boilers94 use these blends.

[tdybr27]

E85 will get you 15-30% worse mileage so it has to be 15-30% cheaper, obviously to make things even.

If you drive in Missouri, you automatically drive with 10% ethanol as it's state law.   I usually just run 87 so I can't help you much in your figures.

[boilers94]

I run E85 somewhat regularly depending on the price and I usually see about a 15-20% drop in gas mileage when I run it.  The E85 usually has to be over $.75 cheaper per gallon before I will even look at using it!  Just my  !! 

[VinnieGTP]

E85 all the time for me now.  11.4MPGs on teh DIC vs 12.7MPS when it was on 87.  It's all city driving also.  $1.33 for E85 and $1.77 for 87 here.

[Donnie1]

We see the same difference with E85 and right now it is only $.30 cheaper so right now it is not worth buying here either.

[FlaBouy]

E85 has makes less horsepower per gallon in laymans terms therefore requiring more E85 to make the same power. On the good side, it has higher octane rating in pure blend than gasoline and therefore is more resistive to KR, which excited most of us HP junkies until we realized it would require larger injectors to spray the same HP levels....

I would suspect you would probably see around a 15%- 20% decrease in fuel economy running E-85....

But on the standard blended gasoline (I.E. 87 octanne, 89 Octane, 91 Octane, etc...) you will not see any difference.... The only way you will see any fuel economy difference between 87 octane and 94 octane on a stock vehicle is if you have something wrong with your vehicle. Sorry, it doesn't work that way. When the manufacturer specifies a octane rating, it is because that is what the vehicle tune has been tuned to.....