Dom said:
IF the proper scoop design
Then the word money come into play.
Not at all, unless you want to spend money frivolously. Research a bit will save lots of money.
Believe it or not those big assed scoops used on drag cars are that way for a reason.
As air flows over the car the layer closest to the body, say about 1/2" thick, is very turbulent. So you have to raise the lowest point of the scoop opening above it.
You then form the rest of the scoop to funnel the high velocity, low pressure air into a convergent path that ends up feeding the intake higher pressure, lower velocity air. Exactly as the guru claimed needed doing. Problem is that none of the factory cars cited do that with thier scoops. That doesn't mean ram air doesn't work, it just means the designs cited are not useful in that application.
That is not to say the design is flawed, it's not, it the application that is wrong. The low drag ducted intakes used on the Firebird and such work great, on a fighter plane where the lowered drag of the ducted scoop far outweighs the loss of ram air effect, but are not appropriate on a low speed vehicle such as a car and I don't care how fast your Mustang is it isn't faster than a P51 Mustang

.
Ram air works, if done right. The examples this guru used are not proof that ram air doesn't work, but rather that the particular examples chosen support a preformed theory of his.
Steve