[lunarhighway]

the problem with conventional radiator setups is they are set up to provide enough cooling under all circomstances. for exmample very slow moveing traffic on a hot day. under most driveing situations it's to big, and sometimes , when the engine is not warmed up for example or in cold weather no airflow is needed.

in perfect setup with curent technoligy what you want is to have an exit path for the air that enters trough the radiator, much linke it was done on WW2 figher planes, however as there where constantly moveing the setup for a roadgoing car might not be completely adaptable,

another solution is to create a variable grillblock, that opens and coloses to allow just enough air to pass trough the radiator to keep the enging at the ideal temperature, but not more.

if you get stuck in traffic the door is fully opened and allows max air to enter to keep your car form blowing up, but when you start the car in the winter it's closed all the time and makes all air pass around the smooth contours of the car.

i like your idea, but i don't think it will work in practive, also the problem in the real world is there isn't enough room in the engine bay of a modern car to make such a duct.

so to summarise my take in this is that, it's a good idea to provide a smooth path for the air that gets into the engine bay, but that it's better to try and keep as much air out of the bay as possible.