I've been burning 89 in my GT since I got it and I simply refuse to soil the tank with that 87 stuff. my last fill up cost me $45...we went to Va Beach this past weekend for the rock n'roll half marathon...and even with some heavy traffic, alittle cruising on sunday evening and trunk full of luggage and running the a/c...the T-Bat still averaged between 26-27mpg...sometimes I just cant believe this car! This much comfort,room and power and still get this kind of mileage (and look good doin it)...man I love this car!...I got to thinkin on the way home tho...if my old man were still around to see how high gas has gone, I'm sure the poor fella would have heart failure...I can remember when he used to fill the family Dodge Polara sedan for 26 cents a gallon.