If you are concerned about Engine Heat the the only real solution is to increase the cooling capacity of the Cooling System. On a temporary fix this can be done by turning the Interior Heating System to FULL HOT with the fans at the highest setting. That can sometimes allow you to limp home a car that has overheated due to sitting in traffic. However the ONLY permanent long term solution is an Engine Radiator with more Capacity, ie. a BIGGER Radiator. In addition a small improvement can be gained by increasing the air flow thru the Radiator by adding some exhaust vents for underhood air but that will only provide a small gain. Another potential gain would be by replacing the bumper bar with a tubular assembly and cutting out all the blocked openings in the lower grill area. BTW, increasing the grill opening count will impact high speed aerodynamics and possibly the stability at speeds over 100 mph.