Tracy
How about ¾” to 1 ¾” is
thin; 2” to 2 3/4” is medium and 3” to 7” is thick.
Aristotle said that virtue is found in the
mean between extremes.
I have an oil cooler that is 3.3”,
and I consider that as thick. It also has minimum mass flow of air and high
delta T (120-140F). I guess it has low drag, but the cooling is inadequate. But
that was subject of a previous discussion. You can’t design an adequate
scoop if you don’t know ahead of time that the airflow is messed up.
Al