Long Tube Headers: Formed Collectors: 3-to-1 mitered collectors decrease turbulence and increases exhaust velocity. The result is increased horsepower, torque and improved throttle response. Optimized Tube Lengths: Tube lengths are optimized for true pulse control technology which improves flow and performance. 3/8" Laser-Cut Flanges: These headers come with 3/8" thick laser-cut head flanges that are designed to match the head port for a leak-free seal. Mid-Pipe: Dual High Flow Catalytic Converters: This system utilizes 400 CPSI (cell per square inch) 48-state legal catalytic converters are used for maximum flow. Construction: Constructed of mandrel-bent dual 1.625" stainless steel piping which transitions into single 2" piping to reduce back pressure and improve flow. Leak-Free Seal: High quality OE style flanges and band clamps are used for a complete 360 degree sealing surface. Hassle-Free Installation: The performance header and Mid-Pipe are designed to fit in the stock location with an included extension pipe which allows this system to fit without modification. This system incorporates OE style hangers, flanges and includes O2 extensions for a hassle-free installation. *All aFe headers and Mid-Pipe systems are engineered and manufactured in our Corona, California manufacturing facility.