Fabspeed Acura NSX TT/Type S Cat Bypass Pipes

Fabspeed Acura NSX TT / Type S Cat Bypass Pipes / Downtubes are a track-focused exhaust-flow upgrade for the 2017–2022 Acura NSX Twin-Turbo and Type S. The system replaces all four restrictive OEM ceramic catalytic converters with straight-through bypass pipes.

The pipes feature a straight-through design developed to maximize exhaust flow and minimize back pressure. With the OEM catalytic converters removed, the system is intended for applications where maximum exhaust flow is prioritized over emissions control.

Construction uses CNC mandrel-bent T304L stainless steel, with precision manufacturing in the USA using Fabspeed's CNC and waterjet fabrication processes. The pipes are engineered specifically for the NSX Twin-Turbo platform.

The system retains provisions for the factory primary catalyst heat shielding and secondary catalyst bypass shielding, allowing the original heat-management components to be transferred to the Fabspeed pipes.

Fabspeed states that the Cat Bypass Pipes reduce weight by 27 lb (12 kg) compared with the OEM NSX catalytic converters. HP and torque gains are currently listed by Fabspeed as TBD, so no specific power increase is claimed here.

The system is supplied with all required hardware and gaskets and is designed as a direct replacement bolt-on application. Installation requires no cutting or welding, although removal of the factory catalytic converters and surrounding components is required.

The straight-through configuration produces a significantly more aggressive exhaust character, with more prominent turbo spool, turbo whistling and turbocharger sounds compared with the OEM catalytic-converter configuration.

Because this product removes the OEM catalytic converters, Fabspeed specifies the system strictly for closed-track and off-road use. It is not CARB or EPA certified and can trigger a Check Engine Light on OBD2-equipped vehicles.