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pdw
07-05-2008, 07:09 PM
In Canada we still see new vehicle window stickers that contain EPA fuel distance in milage per Imperial Gallon or litres per hundred kilometers. It seems to be a bit deceptive trying to make out how much fuel we are actually using for any given distance. All I can really do well is to calculate distance-travelled / money-spent.

United States fuel gallons are approx 1 1/4 pounds lighter.

Is it possible to keep track of exact fueling quantities by their weight ..... ie price/distance per lb?

kwj
07-05-2008, 08:09 PM
The ScanGauge can track quantites in SI units

pdw
07-06-2008, 05:43 PM
The volumeweight in a full tank will change along with fluctuating temperatures, so i find it important to closely guesstimate the ranges in weight that a full tank will vary. A heavier tankfull gives the engine more fuelweight to gobble up, even though the gallon capacity was topped up the same.

90degF - 1.47 lbs-per-litre X 48litres = 71lbs X 11km/lb = 791km
0degF - 1.59 lbs-per-litre X 48litres = 76.32 lbs X 11km/lb = 839.52km

You'll go 48.5km further if the fuel tank starts off full at the fuel temperature of zero Celsius because there the heavier volumeweight contains more fuel for the engine than if the fuel tank was full with 90degree fuel at the beginning of your trip. The engine only knows pounds, but my pocketbook only knows the dollars that the litres cost me.



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