Originally Posted by HeyYou

Just boxing the filter off from the engine compartment doesn't really do much, as the intake is still drawing air from the stock location. Thru the fender. And where does that air come from? The hole at the front, that leads directly to.... the engine compartment.

Rolling down the road, yeah, it should have some benefit, but, around town, or trail crawling, the only benefit you will see if from the better flow capability of the aftermarket induction systems.

A 'real'... cold air induction system, needs to be able to get air that does NOT pass thru the engine compartment. I haven't explored much into this aspect of things for my truck yet, as I currently have bigger fish to fry.