Okay so let me take a stab at it, knowing that I am not a mechanical engineer, physicists, nor did I take thermodynamics.

Disadvantages of a hood scoop:

1. Water and other contaminates (insects) can enter the air filter.

2. Can potential create noise.

3. Block the drivers/passengers windshield view.

4. Add wind drag

Difficulties in hood scoop design:

1. The ram air (speed and pressure to force colder denser air into the hot engines combustion chamber) effect really only works high freeway speeds
or race track unless the shape of the hood scoop is designed to speed air flow.

2. To get the ram air effect, the hood scoop has to be in a high pressure zone which is usually at least 3-5 inches above the hood.
On the surface of the hood is pressure is low and and the ram air is not as effective. GM used the reverse hood (cowl induction) because
there is high pressure near the windshield.

3. Being able to close off the intake at a moments notice from the inside to eliminate rain, bug, or dirt feeding (coming from an 18 wheeler) your engine.

Advantages of a hood scoop:

1. Wow factor

2. Increase in horsepower (5-10 %).

3. Low cost/low maintenance

4. Constant free colder air (than what in under the hood) feeding the hot combustion chamber.

All that being said, deranged said, he noticed a ram port of some sort on the front grill and maybe if that is what it is can create the ram air effect to give that performance advantage that normally real functional hood scoops provide.

My definition of a real functional hood scoop: Orifices on the surface of a hood that take advantage of colder outside air and create a "ram air" effect to funnel to the combustion chambers of an engine for the purposes of increasing horse power.

This is an example of a real functional hood scoop. Notice it is above the surface of the hood by a few inches.

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