This mod lacks the bling of some of the commercial "C"AIs but from what i observed of them they lacked the "cold" part. they all relied on the stock holes in by the radiator cover and the two small holes below the airbox to bring in air. the kay-n-en and that lincoln feller also both had gaps where they could pull in engine bay air when the stock holes couldn't keep up (there's 12 sq inches of cross sectional area in the tube by the TB. i couldn't find that much in total from the stock holes). i have seen many discussions on many boards and claims by manufacturers about horse power increases, whether thru dynos, seat-of-the-pants, drag times, etc. the tests and measurements to back up those claims and the things that are lacking are the "Air Intake Temperature" (AIT) and the pressure drop at the throttle body (TB). the temp can be monitored thru the AIT sensor and the pressure drop can be measured with a manometer at the TB between stock and various other setups. these are the only things that matter and yet not one manufacturer has ever posted such results. in my stock '04 the restrictions were at the Mass Air Flow (MAF) tube and the MAF sensor. the tube on the '04 constricts down in a small square opening plus the accordian creates a whole bunch of turlulence/resistance. i replaced the tube with a 4" ID smooth bore JHP MAF tube. the MAF sensor may get removed if i go to a speed density tune down the road. i replaced the stock panel with a K&N after the stock had 12,000 on it. i figured the long term cost will be less with a reuseable. in actual manometer testing the K&N panel has a slightly lower resistance but the difference between stock, K&N and no filter at all is negliable. anyways here's what i did to really bring in cold outside air. at the strip i really pull hard in the top end with a best trap of 105.99 MPH with all else being stock except for the shifter.
i drilled a hole where the smaller hole below the stock box was. i used a 3" hole saw and had to wedge a board underneath so the pilot bit could center on something. it intersected with the elongated hole that was already there and i used tin snips to cut off the triangle that was left to make an even bigger hole. that's the garage floor underneath.
Then I hacked the inlet "box". it had a baffle that partly blocked the two lower holes. i used foam tape to insulate everything from engine bay heat.
inlet "box" insulated
inlet "box" in car with the hole down below
Modded and insulated filter box. Note i cut that irritating anchor tab off of the front
This shows the insulated IAT sensor
and the finished "snug-as-a-bug" installation