I was wondering what you would chooose as a personal favourite competition engine, no specific race series, just say what what configuration, capacity and aspiration. Considering size, weight, aerodynamics, ergonomics, aural qualities and personal preferance to how your race engine should perform.

I'd choose a Twin turbo 4 litre flat 12, for both aural, power and weight reasons.

Surely you can come up with something a little more imaginitive.

P.S. Fuel is petrol, no hybrids.