Quote:
Originally Posted by elhigh
I'm dying to know what kind of fuel economy this battlewagon gets with a towing ratio in the rear. If it cracks into the 30s, that would set everyone's idea of what a thrifty car has to look like on its ear.
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In my car with the same powerplant, I swapped the auto trans for a manual, which as we all know is more efficient and happens to have a much higher overdrive in my case 0.70 vs. 0.50. It wound up reducing RPM at a given speed by ~500. Which resulted in about a 10+% improvement in my MPG.
I would expect his mileage penalty to be about the same to maybe somewhat higher going from 2.14 to 3.73 rear ratio, as it will raise RPM's by ~750, but I don't think the efficiency losses are quite as high going from lighter duty axle to heavier duty axle as they are when comparing manual transmissions to automatic transmissions.
My manual trans swap also came at a weight penalty as I think the transmissions weighed about the same, but I also chose to upgrade to some heavier duty chassis/suspension components at the same time. So I would say the weight difference between his axle setups would be accounted for in my guesstimate.