Mileage by Brand and Octane for My 1967 Mustang

Gas Mileage

Here's some interesting trivia about gas mileage. Have you ever wondered which brand, grade, or octane rating gives better gas mileage? Well, I've collected thousands of miles of data on a wide variety of brands, octane ratings, grades, etc. All this information is from my 1967 Ford Mustang. I have found these results interesting, I hope you do as well.

Octane Rating by Brand

So, the first question I got from someone when I showed these gas mileage calculations off, was "What about octane of specific brands - that would probably be more useful." So, here it is... Gas mileage results from my records for different brands at specific octane ratings.

Only combinations that have been recorded more than 10 times are listed to try to eliminate deviant results.

Brand	Rating	Number of Entries	Average MPG
Cennex	85.5	29	13.86
Cennex	87	16	13.33
Cennex	88	17	20.55
Conoco	85.5	40	18.42
Conoco	88	15	18.14
Exxon	85.5	20	15.94
Exxon	87	20	16.72
Exxon	88	11	17.55
Holiday	88	12	17.64

I, of course, make no guarantees about what kind of gas mileage you may receive in your vehicle, even if it is a '67 Mustang with an L200 and a couple hundred thousand miles under the hood, because there are way too many variables that come into play...