An air intake is already there on a car. The engine's factory air filter cleans the air as in enters into the engine , and you are usually reminded by the stealership to replace it every 15,000 miles.
A factory engine air intake is often somewhat restrictive for high performance, high rpm work, due to the diameter of the piping, the air filter setup itself, and the various baffles etc., designed to silence some of the engine sound that is heard from that part (not exhaust sound, but some mechanical and other air related sounds as it enters the engine).
An aftermarket intake as I see in this K&N ad banner below my post as I type, will have a larger cone shaped reusable/washable filter. It allows more air to pass through, at the slight chance of also allowing a little more dust into the engine (nothing a regular oil change won't take care of). The piping is also enlarged by a small amount, to allow the air to travel more easily. There are also no real sharp turns or other restrictive design issues with an after market air intake, so airflow is theoretically increased, and as you may know, more air = more power....usually.
The "colder" air (relatively speaking....it's still over 90*F as it enters an engine or hotter) is more dense, so more molecules are present, which means more "stuff" to burn (oxygen primarily). The name "cold air intake" usually means, the kit is designed to suck in air from a lower point in the car (where cooler air is better available away from engine heat). Usually the cone will sit facing the wheel fender well, or toward the front bumper. A "warm air" or "short ram" intake is, as it sounds, a shorter, simpler setup. The piping may only go on to extend around the top of the engine bay still, but because it still uses a cone/aftermarket filter, and the piping is enlarged, you potentially still gain some power.
Now, why do I think that the stock intake in our Coupes is probably still better? Because the stock intake is designed to suck cooler air in from the grill/hood seam. The piping is plastic (which is more resistant to the engine heat) so the air is possibly better insulated from the heat around the engine bay, as it enters the engine. MOST, not all, aftermarket intakes use metal tubing which quickly heats up to the ambient temperature of the steaming hot engine. Also the "short ram" intake, which BTW, is the only type of intake made for our car (due to car's engine bay design issues) sucks in air from around the engine bay due to it's placement....which as you guessed it, is a nice and hot 100*F or maybe a few dozen degrees hotter, defeating the purpose of the "cooler" air theory. However, one can argue that the more free flowing plumbing of the intake kit would still be better overall compared to the stock, somewhat restrictive, air intake.
Ok so all that aside, most intake kits will give your car that growl (from the engine bay, not the exhaust, technically), so it's worth it for that if you really want that.
And yes $200 seems like a lot, which to me is, when looking at the "bang for your buck-meter" but there are far worse offenders, such as cat-back or just mufflers, which can range into the $200-$1000 range for a handful of horsepower (and mostly sound).
