its not just about feeding cold air to it.
as weq said intake length has a big effect. for that size throttle body its not ideal to have the pod stuck straight on.
it's basically the same principle that applies to intake manifold runner length. for example the intake runners on an ITR are quite short which works well for the B18CR. however, sticking that intake manifold on a stock B16A and you're almost certain to see losses in power simply because those runner lengths aren't ideal for that engine.
basically its not a one size fits all, shortest route kind of deal. NA engine draw air in pulses. pulses are essentially waves and waves have wavelengths. length tuning takes into account these wavelengths. of course wavelengths will change with different engine speeds so therefore different intake lengths will benefit different parts of the rev range.
you also have to consider intake velocity. think about a straw and how its diameter and length would affect how fast you could suck liquid through it. too large and too short a straw and you'd struggle. however, too long and too narrow and it would be restricive. its all about finding a balance. an engine works the same........