How much fuel is used globally for car/motorbike/truck races?

Question

I was wondering whether limiting racing would save significant amount of fuel.

For example, Formula 1 cars use about 180 litres for a race of 300 km.

Answer 1

In percentage terms, it's such a small number that I wouldn't worry too much about it.  The racing industry does tend to encourage the use of overpowered engines in cars (think sports cars and muscle cars).  So while the direct effect is small they can have a larger influence ont he overall fuel econmy of vehicles.