Thanks to all. I have fwd this thread to my mechanic. Since the shroud is a full piece of sheet metal behind the radiator with the only hole for the 11" fan I think it makes sense that the air at speed is not sufficiently blowing THRU the rad..so less cooling effect.

http://s1276.photobucket.com/user/Dusty411/media/Radfan_zpscb7c53b6.jpg.html?sort=6&o=0

Last edited by Dogface; 08/28/2013 10:19 AM.
Mark
1949 Chevy 1/2-Ton
Lucielle
Name after my Uncle's Wife..

In the Stovebolt Gallery
More pictures on Photobucket

If there are no dogs in heaven, then when I die I want to go where they went. ... Will Rogers