(Post coffee) Cars have radiators to cool the operating structure (e.g. engine block), but that cooling's ancillary to power produced, no? Carnot cycle was wha

(Post coffee) Cars have radiators to cool the operating structure (e.g. engine block), but that cooling's ancillary to power produced, no? Carnot cycle was what I was grasping for. Original point being that in a thermal engine, increasing your temperature gradient by increasing your high-temperature side (while holding exhaust constant) leads to more potential power. Or IOW, a thermal engine that doesn't burn hot somewhere isn't going to produce much power. (Electric being a completely different ball of wax)