Have you seen the rear flaps on a Top Alcohol Funnycar? That same idea would work on the hood. As far as being a spoiler the underside pressure would have to be far greater then the topside in order to even act in the fashion your thinking about. The only way you could get it to work would be a locking mechanism when the flap reached a predetermined height.[/quote]
Dorian,
I'm sure you're right about all of that. I was more concerned with getting the hot, excess air out of the engine compartment than I was about the spoiler effect, but I know that what you said is true.
Thanks for pointing that out! I should have known that...