Well since we are talking about GXP and the gas milage my mom and I both just ran our cars through the same trip at the same time and and I had gotten a bit better gas milage than her. She drives an 07 GT 3.8 supercharged while mine is a 2007 GXP no mods to air flow or anything aside from that she recently just had her mufflers replaced so she would be louder than me. I must admit though i'm a bit jealous of them.
So does any one have any clue why mine would be a bit more effeciant than hers. BTW both of us run premium fuel
