I have an AirAid CAI that wasn't really a TCAI because the incoming air/filter was still within the engine compartment. After looking at a few ram air set ups I figured I could make mine for less money. For now I wanted to keep the stock air box because I have the URD MAF that is programmed for it. Eliminating that airbox required a re-tune.
1: 3 inch exhaust pipe (14.00$)
2: One 3 inch air duct bracket from home depot (2.99$)
3: One Spectra intake mounting plate from Checkers (5.99$)
4: One Spectra intake tube coupler from Checkers (7.99$)
5: Spray pain (2.99)
6: One flexible duct from from home depot (5.00$)
7: Six self tapping screws (2.00$)
1: Remove Grill
2: Cut a square out of the sheet metal next to the radiator
2: Take your flexible ducting and mock up where you want the pipe to go. This way you can take it to an exhaust shop and they can use it as a template for your permanent piping. When making your mock up put the grill back on so you can make sure it lines up with the middle slot on the grill.
3: Go to an exhaust shop with a six pack of beer, bullshit with the one who looks like a beer drinker, talk about manly stuff, make a friend, go home with your custom shaped intake.
4: Put the intake tube where it will go (if you haven't already cut the tube to size/length this is when you'll do it) and mock up your bracket and air duct plate. My bracket was too big for the pipe so I used some weather stripping I had around to snug up the fit. This turned out to be a plus because it eliminates any possible squeaking from the metal to metal contact on the pipe/bracket. Eventually I will put a nicer bracket in though.
5: Cut out your scoop from the front of the pipe. I had the shop bend out the end of the tube so it would work like a slide for the air.
6: Mark where your bracket and intake duct will go. I didn't have a hole cutter bit, this is why I got the air duct plate. It's easy to cut a square out with a grinder. For the bracket and duct plate screws I drilled a guide hole with the smallest bit I had so the self taping screws wouldn't walk on me when it came time to mount.
7: Mount your air duct bracket and put your coupler on it. Mock up one more time to make sure everything is Kosher.
9: remount/assemble and replace grill
Now I have a ram air true cold air intake. The downside to this set up is the AirAid is not a sealed box, but that can/will be changed soon. All it will take is some sheet metal.
I'll also go to a plumbing supply store aka home depot and get a plug for the pipe so I can close it during bad weather and not suck up the elements.