Well, you're experience is somewhat limitted then.

Granted.

The Navions (and
some others for sure) come with a large intake on the bottom of the
cowl and blow air UP on to the cylinders.

The principle is the same: a pressure differential is created across
the cylinders.

Other planes just blow air
horizontally accross the engine with no vertical separation,

What airplanes?

some just
have the cylinders stuck out in the airstream.

Yes, like a radial in a Stearman, for instance.
--
Dan
C172RG at BFM