This is all insane!!
I find it very hard to believe that you get the kind of mileage.
I just finished a 3000 mile trip on intersate highways and 35mpg was about as good as I could get. In town I get about 33mpg. I've aired up my tires to 40 psi, changed to 0-20 oil. If I try real hard, I can get about 36 or 37 in town but to do that, I find myself driving like an old blue haired lady!

How can your milages be so much higher???