Hooker Max Flow? Sidepipe MufflerThis high performance muffler has been developed for vehicles with 4 inch sidepipes such as 196574 Corvettes or vehicles equipped with Hooker super competition roadster and side mount headers. These mufflers produce an average of 23 percent more power than open Headers and feature a highflow, perforated core that operates at 99 percent efficiency. High temperature packing material absorbs noise while producing a powerful mellow sound. These mufflers,