Parts & Accessories Spare parts Boring and widening air passages. The process of manifold porting and widening the throttle body are mechanical modifications aimed at improving airflow within the engine. The primary goal is to increase the amount of air entering the combustion chambers, resulting in higher horsepower and better torque. Increased power at high RPM: The greatest benefit appears when the engine demands huge amounts of air at high speeds. Faster throttle response: As soon as the pedal is pressed, air flows faster without any obstruction or lag, giving you the feeling that the car has become "lighter".