I have a Stillen hi flow intake w/z tube on my 07 G coupe currently and I was wondering what is the difference, from lets say, an Injen cold air intake? Is one better for performance or sound? I'm mainly concerned with which one sounds better because they are both not going to add that much HP and I'm not crazy about the sound of the Stillen intake.

 

Stillen carries so many variations of intakes and you can see them all by going to www.stillen.com. What I've used for a few years is their z-tube and intake which includes the air box and giant K&N filter. This replaces your OEM air box but receives it's air from the same location. It's made of composite plastic so you won't have heat soak issues. Most CAI get their cool air from the grille area, use aluminum tubes (not good) and allow your engine to ingest moisture if submerged.
Gary