Originally Posted by skalogre
Well, have you noticed that in automotive reviews in, say, the UK, they list how much you fuel consume per 100 km versus how many miles per gallon as over here? I am sure there is some significance to that. Not sure what though.
The only real significance is that the EU96 unit for fuel economy defines it as such. They could have just as easily gone with km/L instead of 100x the reciprocal of that. I don't think MPG/L will ever be a meaningful unit, because it includes factors as wide ranging as the innate efficiency of the engine, gear ratios, unsprung mass, and rolling resistance. Some slow-revving GM slug connected to a gearbox so wide that first is a stump puller and top has you at 1200rpm on the freeway is is always going to seem more efficient on paper than a good engine powering reasonably-sized rolling stock through a well-chosen set of ratios. But in the real world it won't be. If you want better fuel economy, take sensible (and fun-enhancing) steps like lower your car's unsprung mass through techniques such as using smaller, lighter wheels shod with narrower tires. Also, buy the smallest engine for a given chassis.