Its a proven fact that colder, more dense air will build more power.
Now, do I spend the money on a high dollar factory reproduction SS cowl induction style air cleaner assembly, or do I just keep the el cheapo 14x3 on the motor? I'd like to make more power, just curious if this set up really works or if its more for looks.
I already have the "functional" cowl hood with flapper.

IMHO and experience,if you have the functional cowl hood,you should have the correct air cleaner unless you're not interested in the factory look.
I'm just correct that way..it's part of the car IMHO
In regards to it adding more hp you can read another thread in this forum and make your own conclusion.