[425HP409]

Originally Posted by Rufas

The fan shroud is tight fitting around the radiator. The fan is slightly to far into the shroud opening. But because of the supercharger pulley and belt I can't move the fan out any. The fan is less than 1/4 inch from pulley and belt.

You make a good point about sensor location. The high temp I'm worried about is the head temp. So far 215° has been the highest temp, but the outside temp was only 77°. The radiator inlet temp was just under 200°. What concerns me is the summer time temps here typically approach 120°. Most days temp hover around 115°. So I can imagine this condition will get worse.

The problem appears from what you have said is that the fan is too far in the shroud. It must be about half in and half out. By being too far into the shroud, at idle the fan will just cavitate air around in the shroud as opposed to pulling it through the radiator and out the back of the shroud. You also mentioned fan roar, this can be caused by the fan being too far into the radiator causing a cavitation. Since you can't move your fan back, a solution would be to trim the shroud.