> Drove the car to Spencer Iowa and back a week ago yesterday. About a 114 > miles on the odometer, used 9 gallons of gas, that's 12.66 mpg. That sucks! Single fillups aren't always that accurate; youre better off going two or three fillups, just take the first odo reading and the last, add up all the gallons, divide. > Remember it's a stock 304 with the Fomoco 2 bbl, 2.87 gears, G60-14 tires > and T-5 manual with .63 overdrive. I wonder if running in 4th gear instead of 5th would be > better. Gotta get a tachometer so I know what rpm its running at 70 mph. I think G60-14 is 25.8", if so, here's a chart for you. OD= 0.63, 3rd=1.00. 3rd 3rd OD RPM MPH MPH 500 13.4 21.3 650 17.4 27.6 800 21.4 34.0 950 25.5 40.4 1100 29.5 46.8 1250 33.5 53.2 1400 37.5 59.5 1550 41.5 65.9 1700 45.6 72.3 1850 49.6 78.7 2000 53.6 85.1 2150 57.6 91.4 2300 61.6 97.8 2450 65.7 104.2 2600 69.7 110.6 2750 73.7 117.0 2900 77.7 123.3 3050 81.7 129.7 3200 85.7 136.1 Frank sez: > I'm willing to bet you WILL get better mileage running in fourth with > a 2.87 rear axle! When in OD it's as if you had a 2.64 rear axle -- > way to high! Yeah, that's waay too much axle and gears outside of the salt flats... _______________________________________________ Amc-list mailing list Amc-list@xxxxxxxxxxxx http://www.amc-list.com/mailman/listinfo/amc-list