...that if technology could use 100 per cent of the energy of a litre of gasoline to drive a 1,400 kilogram car down the highway at 80 km/h, that car would get an awesome 66 km per litre (or 1.5 l per 100 km)! Or stated the old imperial measurement way: a 3,000 pound car driving at 50 mpg would get 185 miles to the gallon.