Bigger air filters and reduced intake piping can also improve air flow. If the exhaust pipe is too small or the muffler has a lot of air resistance then this can cause back-pressure. Buying a new head that has four valves per cylinder will dramatically improve airflow in and out of the engine and this can improve power. Using performance cams can also make a big difference. Turbo chargers and super chargers pressurize the incoming air to effectively cram more air into a cylinder.
Many manufacturers make aftermarket turbos and super chargers for many different cars.
Cool the incoming air - Compressing air raises its temperature. You would like to have the coolest air possible in the cylinder because the hotter the air is the less it will expand when combustion takes place. Therefore many turbo charged and super charged cars have an intercooler . An intercooler is a special radiator through which the compressed air passes to cool it off before it enters the cylinder. Make everything lighter - Lightweight parts help the engine perform better.