By plastic covers, rubber flaps- what the heck? I would think that the airflow through the radiator would be improved( especially at highway speed) if this stuff was removed. The reason I am concerned with this stuff is that I live in Texas(hot) and when the outside air temp is near 90 degrees(always) my engine won't run at the 180 degrees I have it set up for. The car is definately faster when running below the temp gauge's half way mark. I even leave the A/C off to keep the temp lower before a fun spurt( of course I turn off the A/C while full-throttle). So I'm trying to improve the cooling ability of the radiator. Any tips on improving the cooling? -Jeffy.

 

Replace the lower restrictive grille with something else.

 

Removing the 'flaps' and leaving the shroud open will actually decrease cooling effectiveness at low speeds or with the fan. Since the fan does not cover the entire area of the radiator, a shroud is used to 'focus' the airflow and help the fan pull air through the entire area of the radiator. Because the shroud becomes a liability to airflow at highways speeds, the 'covered' areas are fitted with doors that are blown open by the airflow pushing through the grille and radiator. At low speeds or not moving at all, the doors are closed. If you remove the doors completely, when the fan runs the openings in the shroud will greatly reduce the fan effectiveness, perhaps to the point of your car overheating in traffic.

The reason why your car runs 'hot' (I assume you have fiitted it with a 180degree thermostat?) at low speeds or idling is because the fan itself is not programmed to come on until the engine temp is a bit over 220 degrees. The fan will shut off after the engine temp falls to about 200 degrees. If the system senses that the fan is having difficulty keeping up with cooling off the engine, especially with the a/c engaged, the fan is kicked into a second, much higher speed. This should have no problem at all keeping the engine from overheating in even the hottest of weather.

If you want to keep your engine cooler when not moving, the fan can be 'hotwired' to run at the flip of a switch if you (or someone you know) is good at electrical wiring in cars. The only problem here is that sometimes a code will get thrown saying that the engine is below operating temp.

A splitter mounted under the front lip helps to funnel more air into the lower grille opening, and an aftermarket grille can also be used to open up the airflow at speed.