Every Engine needs a good source of clean air for breathing and this is the job of the air filter to provide that. A good breathing engine will enhance the combustion taking place. When it comes to breathing in engines, they are divided into two groups; Natural aspirated engines and Force aspirated engines.

The natural aspirated engines are those engines that suck in air by gravity; this is due to the downward movement of the piston during the induction stroke. It is with this movement that the engine takes in air for combustion.

The force aspirated engines are those engines that have air forced into them by the aid of a mechanical device known as the turbocharger. The turbocharger increases the air intake of the combustion chamber thereby increasing the power output compared to that of the natural aspirated engines.