1.As you can see here, the factory unit leaves little to be desired. It is made of black plastic and is bulky and just not very cool in general. Stock units have a number of hang-ups in that they almost always use a paper panel filter and sound-reducing chambers, both of which hinder performance. Chevy did go so far as to incorporate a plastic intake manifold to reduce air-intake temperatures. Now, a quality intake will finish where the company left off.