NACA and NASA studies (Miley) have shown that this method generates a
little more drag than an equally engineered "normal" cooling.
----------------------------------------------------

Also, the draft of the VW's head castings show that the direction of
the cooling-air flow was taken into account when creating the
demountable, permanent molds. Just another of the 'unimportant'
details that tend to get overlooked (or deliberately ignored) when
converting the VW for flight.

-R.S.Hoover