I've been thinking about this exact same idea for some time. I have an aversion to adding anything non-functional to a car, so if I ever switched over to a shelby style hood, I'd want it to do something besides provide clearance for the air cleaner wing nut.
The scoop isn't big enough to provide a true ram air effect. However, I think it could very well provide a cooler, denser air charge under certain operating conditons. This has been used on other cars in the past. For example, my 1983 Trans Am had factory functional rear facing air scoop that opened with the 4-barrel to provide cooler dense air from the high pressure area at the base of the windshield.
So, I think you could make a functional hood scoop to supplement the air needs of the engine.
1. Open up the hood scoop on a shelby style hood.
2. Cut an opening in the air cleaner lid.
3. Fab up a seal, to seal between the engine and the hood. The key would be to make this look "factory" as opposed to looking like the seal around a window air-conditioner on an old trailer.
4. A solinoid actuated flapper, working off a micro switch on the throttle rod would be extremely cool.
5. Consideration would have to be made to directing the air from the hood scoop through some filter. This could be a thinner secondary filter built into the seal, rather than the main air filter. Because this filter would just be open at WOT or when the secondaries were open, it would not get nearly as much use as the main filter. Thus a thinner media might be justified. You could even use a defeat switch in the cockpit so the driver could kill the scoop during rainy or dusty conditions.
Now, although I do think this would be neat and everything, and would make the hood scoop "functional", I would NOT expect any dramatic power gains. I would guess 3 - 7 horsepower at the crank.
So, it'd be a 9 on the "coolness chart"
it'd be a "2" on the "useful chart"
Keep thinking though. If you decide to do it, make sure you take pictures.
Phil
'65 Convertible (with many mods.)
http://www.blueriver.net/~finite/Pony.htm