I get about 12 MPG with a 60/40 mix of highway/city miles. I have a k&n on custom piping, bored out throttle body, port matched manifolds, port and polish, 3-angle valve job, polished combustion chambers (i'm going down the line of where air goes, heh), highflow cat to a flowmaster. Countless other free and cheap mods.

Oh yeah, 93 cherokee with 31' swampers and 3.55's.