what kind of gas mileage out of your car

[chpr1972]

It seems that no one is concerned about gas mileage. But for a lot of us, gas is part of the free money left over from the weekly expenses. It is a difference between a Sunday afternoon cruise or a drive and set car show, or stay home. So, I have access to a 2003 Suburban with a 5.3 aluminum motor and probably a 4L60 transmission. So mileage is part of my concern, but an LS is an ugly motor to a old skool guy. If I can pick up 5+ mpg [14.5 on highway at 70 mph] then I will spend the money. I have to go to an automatic, and 4L80 is a expensive swap into a non computer car. [400R4 is not capable to handle my torque] I think a lot of people would be interested in gas mileage even if it is a secondary consideration.
66 Lemans convertible w/A/C
BBC 489
HP EFI TPI tunnelram w/2 throttle bodies
10:1 compression
282/288 .510/520 lift comp roller
ported close chamber heads big valves
TKO600 5 speed
3:70 Ford 9"
25.5" tires
8/10 mpg in town[ some? spirited driving ]
14.5 mpg highway @70 mph