most are apparently now pushng out towards 900 bhp (according to Brundle at the Chinese F1)- that's an incredible 300 bhp / litre.

the best n/a road car production engines push out about 120 bhp/litre

of course in the turbo days, they were said to have 1500bhp from 1.5 litres in qualifying spec - that's 1000 bhp/litre didn't last long though