Originally Posted by Redsand
Jeeps never get good mileage, they push too much wind
Compared to the 7mpg I was getting. 16-20 is heavenly.
But I have to disagree with intake and exhaust worsening mpg.
If you get a tuner, intake and exhaust. You will, at least in my experience, gain a couple mpg.
Engineers have to keep volume in consideration when designing the air flow through an engine. To quiet an engine requires restrictive measures. The general public usually doesn't want a loud vehicle, so the engineers have to play a balancing act, you do not.
I can tell you now that to get the volume down on the v6, requires significant restriction to do so. My 350z is a 3.5l v6, and though the vq36de is inherently a louder engine than the pentastar, my 350z is deafening in comparison. Sometime I can't even tell of my jeep is even running.
Just my opinion, but if you didn't give a crap about volume, deleted the muffler entirely, ran a true dual 3" exhaust with long tube headers, routed the intake out of the engine bay and behind the bumper, then bought a programmer and tweaked it, you would definitely pick up a few mpg. But it would be SIGNIFICANTLY louder.