Upgraded Intakes draw a larger volume of cool air from outside the engine bay than stock intakes. They are especially beneficial for turbocharged engines for two primary reasons: increased volume of air at intake and decreased intake air temperature.

Increased Volume of Air at Intake: The turbocharger's ability to "boost" is dependent on airflow from the intake. With increased air flow, the turbocharger can compress more air into the engine (if the air is cool). This results in higher boost pressure, enhancing power output and overall engine performance. A steady and ample supply of air to the turbocharger also allows it to spool up faster and deliver boost more quickly.

Decreased Intake Air Temperature: Turbochargers have to work harder to compress hot air than cold air. This impacts turbocharger efficiency. When intake air temperatures are lower, the turbocharger can compress more air into the engine, resulting in higher boost pressure and increased power output. High intake air temperatures can increase the risk of detonation (knocking), which can damage the engine. To prevent damage, the engine management system may reduce boost pressure or adjust the ignition timing, leading to a decrease in performance. This is called a "safety."