997/991 GT3/RS – Active Side Muffler Bypass Pipe


More Sound. More Power. No Drone.

TPC Racing Active Side Muffler Bypass pipe provides Cup car sound and weight reduction of 36 lbs. The active valves work in concert with the car’s existing sound control system to provide both powerful Cup car sound and street civility with no cabin drone. The weight reduction improves handling and acceleration performance. The rear tire pressure/grip becomes more stable without the radiating heat generated by the bulky and heavy OEM side mufflers. The external temperature is reduced around the valve cover and the ignition coil areas.

How it works

Using a factory-style actuator-controlled valve, the TPC Racing Active Side Muffler Bypass System provides Cup car sound and exhaust flow performance in higher rpm/higher load ranges, while eliminating unwanted cabin drone and excessive noise. Its lightweight design saves 36 lbs from the OEM side mufflers, resulting in improved handling. Better exhaust flow management allows for increased torque between 2,600 and 5,600 rpm, as well as increased horsepower between 5-8,250 rpm.


  • 36 lb. Weight Reduction from OEM
  • Factory-Style Actuator-Controlled valve
  • Metal Flex Joint for Easy Installation and Reduces Chance of Center Muffler Fatigue
  • Metal Flex Joint is Protected by Stainless Steel Braided Covering
  • Beautifully and Robustly TIG welded by Master Welding Technician on our precise Jig Fixture
  • Each Unit is Handmade in the USA at TPC Racing, 100% Smooth inside the pipes and in merge areas, consistent inside diameter throughout the entire pipe
  • Stainless steel material is X-ray tested and exclusively from Woolf Aircraft Company made in the USA


Experience cup car sound and performance for your 997 or 991 GT3/RS, while eliminating unwanted cabin drone!



Additional information

Weight30 lbs
Dimensions18 × 15 × 12 in