Now that we've discussed what an air intake does and how an aftermarket intake might actually hamper your vehicle's performance if the necessary adaptation steps are not taken, let's have a look at what type of intakes are available in the market today.
Generally, there are four types of popular aftermarket air intake mods that you can widely purchase for your car. They are; Cold Air Intakes (popularly know as CAI), Ram Air, Short Ram Air and Performance Drop In Air Filter.
Cold Air Intake
Cold air intakes are air intake systems that suck cold air from outside of the engine bay instead of the hot air cooked up in a closed engine bay. With the logic that cold air is denser, which carries more oxygen, it helps the engine create more power. This type of intake will give you better engine performance, but the common problem with this type of intake if not appropriately engineered is that it can cause hydrolock, a process where the intake sucks in water which is a big no-no for the engine. Stock air intakes are already CAI type intakes as they utilise the grille for cool air.
Ram Air Intake
If the hint is not in its name, this air intake rams air into the engine usually by routing the piping to the front of the car right in the path of travel and fast incoming air. Usually, air is rammed through a scoop at the front somewhere. The logic behind this intake is to push more air into the engine instead of the engine sucking it in. They are usually most effective at higher speeds as the air needs to be pushed into the intake system. In theory, the fast air is pressurised in the intake system, which acts as a small turbo or supercharger. While this sounds like a recipe for more performance, daily driving in slow traffic could actually hamper your car's performance as not enough air is being pushed into the intake system.
Short Ram Air
Although the name might suggest it is just a shorter version of the Ram Air intake, the SRA works slightly differently. The SRA is basically a short pipe near the mass airflow sensor with a conical filter attached at the end of it. The shorter pipe increases throttle response and provides one heck of a noise. Unfortunately, this is as good as it gets for SRA systems because it mainly sucks hot air from the engine. Perhaps a turbocharged car can do away with the hot air as it has to go through an intercooler anyways.
Performance Panel Filter
A performance drop in air filter is basically a drop in air filter shaped like the stock filter but uses different material to filter the air. The material used to filter debris and dust on a stock filter is paper while many performance air filters use foam, mesh, etc. Theoretically, it does let more air in, but the downside is that it tends to let more than just air into your engine - like dust. Some performance companies have created a hybrid version which promises to filter dust, but do your research before you purchase one.
To decide which one might be the best for you, a good place to start looking are the forums. They have extensive conversations about air intakes and cover subjects such as fitment, performance, fit and even sound. There is an intake for everyone, but be warned, the best intake if you are not planning to do any other modifications to your car is probably stock. Whatever you do, just make sure your engine doesn't run out of breath.