I’m not trying to be negative but what is it’s CFM when you throw a radiator in front of it. When I had the 2+2 I bought a sheet of aluminum and what I thought was a decent 16" fan. I fabricated a shroud and installed the fan. I had no data to back it up but my impression from the temp gauge was at best I’d equaled the factory setup.
For grins I built a 3" long wind tunnel with a 12"X12" cross section to compare 10" cooling fans. I placed thin wires at the outlet end of the tunnel to give me 9 reference points to measure air speed with an anemometer . The airspeed will vary at each point but I figured I had enough points that I could average them and get something meaningful. I compared the square motor with the stock blade to the round motor with the stock blade to the round motor with an aftermarket blade.
The square motor moved the least amount of air, the round motor with the aftermarket blade moved the most air and the round motor with the stock blade fell in the middle. All were 10" fans that fit in the stock shroud with the divider installed between the two halves.
I’m running the round motors with aftermarket blades. The engine was rebuilt 5,000 miles ago, the cooling system is clean and stock, antifreeze is a 50/50 mix. I poured in a bottle of Water W#etter, figuring it couldn’t hurt, but in reality I probably just wasted the money. With the AC on, sitting in traffic in 98 degree heat, the coolant temp never has gone above the “L”.