so i tried this little experiment to see if it helps my gas mileage. i was averaging 27 mpg, and 50-50 city/hwy.
been using 87 since i got the car about a couple months ago, although i did tried a tank of 89 to see if it helps with the mileage. i'm not sure if it's coincidental, but when i filled it up with 89, my mpg went up to 31mpg. i switched back to 87, and my mpg went down to 29. well this last fill up i decided to go 91 from walmart (murphy gas). it went up to 34.5. i will try another tank to see if i can maintain this kind of mpg, or improve it some more. the way i look at it, i'm saving money even if i'm using the premium gas. if i can increase my usage to at least about another 40 miles per tank, that's a little over a gallon more. comments?