Originally Posted by StangNut
There's not much you can screw up when making a CAI. It's simply a tube, a rubber elbow, rubber sleeves, clamps, a heat shield, and an air filter.
I'd stay away from anything with a metal intake tube though. They transfer more heat to the incoming air than plastic ones.
Actually there is a great deal you can screw up with a CAI. If the MAF housing is off even the slightest bit (sensor depth or angle) you could have all sorts of performance issues.
And don't get caught up in the metal vs plastic debate. IATs with metal tubes aren't significantly higher than with plastic tubes.