quick question

Yup...freeing up a little exhaust flow helps too. Just remember, with new found power, comes a new found urge to test it out at every stop light. Although you mileage will technically improve under normal driving, you need to remember to discipline yourself in order to actually improve it.

If you spend the majority of you driving around town and in stop and go traffic, a gear swap to a higher (numerically) set of rear gears might actually improve your mileage as well. It’ll hurt you a little on the highway, but the added torque multiplication down low and ability to frequent overdrive more often will often improve your situation around town.