Invidia high flow cats are constructed for the serious automotive enthusiast. The factory catalytic converter is basically a screen that heats up to burn off excess fuel. This screen also slows down exhaust flow, chokes off your engine, and reduces noise. Replacing the factory unit with Invidia's high flow cat is yet another important step toward maximizing exhaust flow and performance. Invidia's high flow cat replaces the factory unit with freeer flowing unit to increase exhaust flow and offer a more raw sound. The high flow cat is perfect for drivers who seek an exhaust note that is slightly less extreme than a catless exhaust system. The best feature of a high flow cat is it offers more horsepower and torque than the factory cat while retaining the driveability of a catted exhaust system.