nonsensez9

not specifically the KB CAI... however that one probably has the benefit of cooler air - though I won't be satisfied until I actually go out and measure the temps - but let's assume that it does. There are a few things working against it, too:

1) longer tube - the longer the tube, the more power it consumes pulling the air through the tube = parasitic loss
2) longer tube - the air will "stretch" inside the tube - the longer the tube, the more the air "stretches out" for lack of proper scientific language. So the 2.4 litres for each revolution of the screws might only be 2.3 litres of "unstretched" air
3) longer tube = more turbulence = more heat
4) bends = more turbulance = more heat

at some point, if you add enough tube and/or bend in the tube, the benefits of the cooler air are going to be cancelled out. My original question becomes "how much tube does it take to cancel out the benefits of the cooler air?" is it at 10 feet, 100 feet, 2 miles?

My understanding of typical CAI's - K&N for example - is that the power gains is not so much from additional air, but rather less parasitic loss. The car was getting as much, or nearly as much air with the standard air box, but the motor had to work harder to get the air pulled through the restrictive air filter and the long bendy tubing.

Arrow

Don't forget that the relative density of the air in the intake pipe is not only dictated by the length of the pipe, but by the diameter of the pipe, too.

I'm way too sober to attempt dredging up the old equations for volumetrics, but it goes something like "a pipe with twice the diameter can hold twice the volume with half the resistence."