MAD BMW F90 M5 F92 M8 Primary Catted Downpipes S63RIntroducing the M5 M8 Primary Catted Downpipes the ultimate upgrade for enhanced engine potential, increased power, and torque throughout the RPM range. Constructed from top quality T304 stainless steel, these downpipes are designed for longevity. Mandrel bent for optimal flow, they feature smooth transitions to minimize turbulence and improve exhaust gas flow, resulting in noticeable power, torque gains, and a more aggressive exhaust note.