Jeff,
If you shroud the cooling fans and not the radiator, you will effectively force air around the radiator--which is not good. The increased resistance to air flow (by the shroud around the fans) will allow to follow the path of least resistance, or around the radiator.
We do not use shrouded fans, as I mentioned above, because the actually block air flow at high speeds (like on a race track). Many, many of our customers take their cars both on the street and the track. Tracking our cars is becoming more and more common. It is just too much fun.
We do not run thermostats on our
oil coolers for the big block cars. On small blocks, we simply block off the
oil cooler until we are fortunate enough to get some rubber on the track.
David
