The 034Motorsport Stainless Steel Racing Catalyst for B9 Audi S4/S5 is designed as a drop-in replacement for the restrictive factory catalytic converter. The Stainless Steel Racing Catalyst offers increased horsepower and torque throughout the powerband, reduced turbocharger lag, improved throttle response, and an enhanced exhaust note.

• This product is sold for off-road use only.
• By purchasing this product, you understand this product is sold for competition use and is not legal for use in highway or street vehicles.
• This product will cause a check engine light (MIL) on the stock factory tuning. A racing ECU calibration for offroad use only is required to eliminate the check engine light.