A dealer tech friend of mine used to illustrate the issue by taping a fan blade to the shroud with a length of 3/4" masking tape. Start the motor and see if it will pull the tape loose....you might be surprised. Several that wouldn't pull the tape loose, even at rpm above idle, would feel "tight" when spun by hand.

I used to stop them at idle with my hand, gloves on. showing how a clutch should operate, but one of my techs whack his finger hard showing how I did it to another tech on a car with a bad clutch.

You could tell the clutch was fully engaged (full size truck) as it was pulling in some serious air.

I'm just a little more careful as to what I say to others now.

thats the way i allways checked them

glove and try to stop the fan

I always ran the aluminum rads like summit sells and I would only see 200+ sitting in traffic on hot days. No shroud on any of them. They sell aluminum rads with brackets already mount that bolt right in the stock location for around 200. To me that's the way to go.

A couple of lessons from my own experience:

1) Distilled water and a bottle of water wetter will keep the temperature lower than a 50/50 mix of green antifreeze/coolant. The antifreeze holds (retains) more heat than straight water. Straight water cools quicker than ethylene glycol (mixed with water or unmixed).

2) In the middle of Superbird production (late 1969), the factory engineers changed (on 440 motors) from a clutched fan to a direct-drive fan (no clutch) due to Bird cooling issues at "highway speeds". Thus, a direct drive fan helps pull air through a radiator better than a clutched fan - shroud or no shroud - at highway speeds.

3) When you have the money available to buy that Glen Ray Radiator...DO IT. Using a 26" Glen Ray Radiator, and distilled water and a bottle of water wetter...I had to "work" to get the temp up to 180 degrees on my Super Bee. Glen Ray builds a helluva radiator.

my 383-4v likes running "hot" even with a new radiator, clutch fan etc.
this is what helped me.
I got rid of the 7 blade fan and went to the FIVE blade fan (that looks real weird). The idea being when you are at engine cruising speed (70 MPH) the 7 blade fan is like a garbage can lid and will NOT allow enough air to flow THROUGH.
Also, be sure you buy a Hayden brand fan clutch (if so equipped). The water pump is available from Summit or "the brassworks" in CA. The clutch is available at NAPA. The fan I bought at a mopar dealer.
I also bought a flowKooler brand water pump that has larger impeller blades and an anti-cavitation plate on the back of the impeller blades.
I run 50-50 antifreeze/water and I added some water wetter of some type as well.
With my factory air on, and it is 100 outside (Phoenix, AZ) and I am cruising, I will be about 200. It used to be 230.
HTH
Bob