Its a functional ram air intake. This means instead of the engine sucking air in with a normal GT's intake, cooler air is forced in through the hood scoop into the intake, and airflow is improved. The faster you go, the more air is forced into the scoop and helps keep the engine breathing strongly. Besides looking awesome, it is a great air intake system.
2003 Mustang GT, Cold Air Intake, Ford Racing 70mm Throttle Body, C&L Trueflow Upper Intake Plenum, Pypes Catted X-Pipe, Pypes Violator cat back, 3.73 gears, Diablosport Predator Tuner, Tri-ax Shifter, Steeda UDP's, Mach 1 chin spoiler, Mach 1 grille delete, H&R lowering springs, Electroluminescent gauge face , Bullitt pedals