Originally Posted by imag

Engine bays have no real problem with water (as long as it doesn't snorkel in the intakes, obviously). When driving, air will be exiting through the vent anyway.

I'd be into venting, but wouldn't do it for the weight; I just don't see how you could lose much weight in aluminum. I'd think you'd be much better off with a good carbon hood, which they'll no doubt have out shortly.