Do you really think a car manufacturer in modern times would fit something that would honestly cause a car to run hot? More so on a sports model which has been designed with track work in mind? Also have you thought about what happens when the car is actually moving? Air at 30-100mph moves quite quickly, it runs through the engine bay too you know!
Leave it on, it won't make any difference to heat, it will just make your car dirty and probably a little slower.