Who knows what goes through the minds of engine engineers these days? – or 40 years ago for that matter. In order to get the maximum performance from an engine, it has to be able to breathe. It seems that every car I've ever owned came with one nostril with a clothespin on it (metaphorically speaking).
While I had the air intake system apart to get to the Intake Air Temperature Sensor to install a G-Force Performance Chip, I decided that I would save myself some work by also replacing the factory air intake system while I was at it.
Look at the left photo below. There is a huge air filter box with an accordion-style rectangular filter (ACDelco A1548C Air Filter) with lots of surface area. The box is connected to an air horn that is about 1½ inches in diameter. At highway speed, this is like a running cheetah trying to breathe through the snout of an aardvark.
Removal of the stock air filter box involved drilling out several heavy rivets inside the box, and cutting off their "nubs" with a Cut-Off Wheel on a Dremel Stylus Tool fitted with a Keyless Chuck.
Now look at the right photo below. There is a huge space on the fender well where the original air filter box used to be (nice place to put a kick-ass, 4-trumpet air horn in the future). The Spectre Filter attaches right to the original hose that connected to the old filter box with the included adapters. The 4-inch diameter hose lets the engine pull as much air as it needs. The filter itself just hangs there, so I secured it to the Crossbar with a heavy duty Zip tie.
The Spectre Performance 8138 White/Chrome Cone Air Filter costs about twice as much as a replacement for the "stock" filter, but when it gets dirty, you just pull it off and clean it out with a garden hose. This is a "no-brainer"; just like NiMH Rechargeable Batteries instead of single-use Alkalines, or a decent water filter instead of bottled water at a dollar a pop.
The performance, and gas mileage improvement this gives you is IMMEDIATE.
By The Way... this type of air cleaner is used by many Jeep and Hummer owners for their DIY
If you are looking for a "factory" snorkel kit, try one of these