Many know I have written extensively about engine cooling and cooling drag. 

 

Probably too extensively with the result that many have been left in the snow drifts as shown by the recent 320 cooling discussions.

 

Let's try this and see if it helps: all described in one single diagram for those (like me) that prefer pictures to floods of words and numbers.

 

Have a look at the attached figure and see if it helps.

 

Fred