[cubber]

I have run my switch in both the intake, and the head. I even had it down lower on the block in an I6 I had. I never had a problem with ANY of these locations. Once your t-stat opens, which it will do WAY BEFORE your engine temp gets into a dangerous range, the water is flowing through the whole system, and is probably close to the same temp. everywhere except where it leaves the radiator. I think that there isn't a nickels worth of difference in any of these positions. Your engine is water-cooled, and the water is cooled by passing through the radiator. Any sort of fan, electric or mechanical, or any sort of shroud is just a way of accelerating air across the radiator fins, thus cooling the water in the radiator more quickly. Some are more efficient methods. I too have a high dollar 383 and would not be afraid to run my switch in any of the previously mentioned locations.