Hey all, I'm new to this forum and to Mustangs in general. I picked up a 2006 GT Automatic with 67k miles on it in November. I just started driving it this week, as I did a lot of work on it during the winter. I'm only getting 13 MPG right now. I do a mix of highway and city driving, and I drive conservatively 90% of the time. The mods I have are a JLT CAI, BBK longtube headers, off road x-pipe, cervini side exhaust, and a custom dyno tune. The car is making 425 crank HP if that matters at all.