Km/l was commonly used in Europe, but was changed to l/100km in the 90's I think.
I blame EU
As long as you keep it metric, I'm not bothered.
But then again, you might want to have as an option to change between metric and imperial measurements, as most people have no clue about other systems. (I mean all measurements in the game will be metric or imperial.)
This will also solve the annoying thing, when you create a chassis with xx" Width for engine, create an engine which is xx" and it doesn't fit because it's several mm too large.
I blame EU
As long as you keep it metric, I'm not bothered.
But then again, you might want to have as an option to change between metric and imperial measurements, as most people have no clue about other systems. (I mean all measurements in the game will be metric or imperial.)
This will also solve the annoying thing, when you create a chassis with xx" Width for engine, create an engine which is xx" and it doesn't fit because it's several mm too large.