I am getting an average of 28 mpg. That is average over the past 2-3 months. On the last trip to Canada (330 miles or so), I got an average of 32.8 mpg. And if I was doing all highway, I am sure I could get 34+.
But the tune helps considerably. I was only getting 25mpg MAX (avg 20-22) before I tuned it. So the tuner has more than paid for itself.
But I also agree that the heat doesn't have anything to do with it. My car gets better fuel mileage in the heat than in the cooler temps. Days that reach 90° give better economy than ones in the 70s.
Also, I drive 100+ miles a day. I keep extensive records, much like scotty. I put everything into an excel spreadsheet, since I always have my laptop for my tuner, so mileage and trends are very easy to compute accurately.
