"racing" ... in competition then engines pretty much return the same consumption whether it's racing or rallying.
The reason is it's mainly wide open throttle and hard acceleration.
The engineering in the "ancient Mini" is copied TODAY !
And the Escort Twin CAm engine is not a million miles away from again modern efficiencies ( taking fuelling otu of the equation as modern injection and emissions control makes a difference )
So the "Logic" is fine .. just the "practical experience" you still have to pick up.

PS: I've not flip-flopped. YOU only said f'ing "displacement" and only when challenged/explored do you now claim always knowing the other 2. Thank you google