1972 454 mileage question
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1972 454 mileage question
Have factory stock 1972 454 auto. After professional rebuild of carb my gas mileage has increased and is now 7 mph. (was 5). Will changing rear end gearing significantly help? Any suggestions? Thanks.
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If the rear gears are stock, you most likely have 3.08 but an optional 3.36 was available. Both are considered economy/standard gearing, so changing out to something else isn't going to do much for you.
7 mpg is horrible if you don't have your foot in it like a 16 year old. When I used to check mpg, my '72 454, auto, got in the 13-15 range around town. I agree with Motorvation that a complete tune up is the first thing to look at. With the carb rebuild (what carb is it?) put in fresh plugs and run it for 50-100 miles, then pull and "read" them to see how the engine is performing as to air/fuel mix and combustion characteristics.
7 mpg is horrible if you don't have your foot in it like a 16 year old. When I used to check mpg, my '72 454, auto, got in the 13-15 range around town. I agree with Motorvation that a complete tune up is the first thing to look at. With the carb rebuild (what carb is it?) put in fresh plugs and run it for 50-100 miles, then pull and "read" them to see how the engine is performing as to air/fuel mix and combustion characteristics.
