Good Grief.

So many comments, so little information.

It's really quite simple:
Either coolant flow is adequate, or it isn't.

"Running something at 2-- degrees" and the engine's relative happiness or unhappiess doesn't account for where the temp is measured.

Does anyone believe that the location in the water pump where the sensor is located is the be all, end all?

It's not that a 440 "doesn't like" the temp being at
200-something degrees---they will, in fact, run hundreds of thousands of miles if the true coolant temp at the hottest point in the engine is 210 to 220. The problem is that the coolant temp isn't being measured at it's hottest point, and we don't know what it is at the hottest point when driving down the road.

What do all the gurus think the coolant temperature is in the middle of the cylinder head, where two exhaust valves are located right next to each other? How about inside the block, directly below that area? Here's a hint: It's a whole lot hotter than where the temp is measured at in the water pump!

The water pump housings in question sound screwed up to me, I either use stock ones or MP Aluminum.... but beyond that most of this discussion seems kinda hopeless....I mean...Older cars worn out at 70k miles? WTH does that have to do with a coolant temp discussion? My 176,000 mile '78 B body and my 210,000 mile '83 M body kinda kill that statement anyway. If all your stuff is worn out at 70k miles, you're doing something wrong