Originally Posted by Noah
Originally Posted by Michael H

Technically, it is an oil cooled engine with air fins as a bonus.


It's the fins that actually transfer engine heat to the environment.

The important thermal function of the oil is to keep the areas around the combustion chamber and exhaust valves from overheating by transferring heat to the cooler parts of the engine, the fins on the head in particular.


Don't forget all the bearing surfaces without which noting else works.

The light at the end of the tunnel is actually a train. 2019 M3W