What?!
The shroud is on the backside of the radiator. It's not blocking any incoming air at speed. The puller fan draws the cool air through the shroud at low speeds. This is a proven system that literally every radiator manufacturer uses.
If you're speaking to the fact that I didn't incorporate louvers into the shroud - louvers only help when the fans utilize < 60% of the shroud's surface area. Hence, why I purchased the largest fan I could find. My fan takes up 75%, thus not necessitating louvers for proper heat exchange.
I live at 4300ft in the high desert where Temps stay above 100°. My engine is 12:1 421 stroker and the coolant has never been above 185° at the track.
The setup works well. Plain and simple.