If I understand correctly, you're basically making a cold air intake without the piping.
If that'* the case, there'* no point. All you'll be doing is sucking really hot air out of the engine. That will probably hinder your performance more than help it.
The idea behind a CAI is to pull cold air from the front underside of the car, before it has a chance to get heated by the engine.
Some Vibe owners have installed short rams, and then run a secondary hose from the front grille to the short ram.
Kind of accomplishes the same thing, but I think it isn't nearly as good as a full CAI would be.
But I think a CAI looks, and performs, better.