Performance Catless Test Pipes | Audi B8/B8.5 S4 S5

Catless test pipes for the B8/B8.5 Audi S4 and S5 replace the restrictive factory catalytic converters to maximize exhaust flow, sharpen throttle response, and deliver noticeable gains in power and sound. Built from TIG-welded stainless steel for durability and direct bolt-on fitment, they’re designed for high-performance or off-road use and may require proper tuning to prevent a check-engine light.