Coolant flow

12many said
Huh? If a radiator can’t keep up? Have you any experience with such a scenario? I do. Undersized radiator for the application is more fitting.
Then you want as much air flow unimpeded: no flat shroud and/or electric fan that has a bulky blade blocking air flow, a good mechanical fan, (fixed or viscous) as big as you can fit, a high flow thermostat (I run a disc akin to a gutted 160° no bypass hose etc) and high flow/volume pump. No slowing down anything.
I have vast experience with what it takes to make a stroker (not to mention other Mopars through the years) with an undersized radiator (18”x18”) in an oppressive compact engine bay with less than ideal frontal air intake run cool trust me.

Move the coolant, move the air. Period.:BangHead:

If you think an electric fan on the backside of a radiator is going to reduce airflow more than the resistance from the radiator itself, you weren’t paying attention in your fluid dynamics class.

If you put a big flat pan on the back of the radiator like some of the poorly thought out aftermarket electric fan shrouds you can cause issues. But the fan itself isn’t a problem, and neither is a well designed fan shroud.

The idea that you have to run a mechanical fan for best cooling is antiquated at best.