991 GT3/ GT3 RS Side Muffler Bypass Pipes 2014-2016 #FS.POR.991GT3.SMB

Fabspeed Porsche 991 GT3/ GT3 RS Side Muffler Bypass Pipes from NemesisUK
Fabspeed Porsche 991 GT3/ GT3 RS Side Muffler Bypass Pipes from NemesisUK 1
Fabspeed Porsche 991 GT3/ GT3 RS Side Muffler Bypass Pipes from NemesisUK 2
Fabspeed Performance Exhaust Side Muffler Bypass Pipes - Non Valved Porsche 991 GT3 2014-2016 #FS.POR.991GT3.SMB


Available for pre-order

Side Muffler Bypass Pipes for

Porsche 991 GT3 Performance Exhaust

Optimised design that replaces the heavy and restrictive factory side mufflers for improved exhaust flow, increased sound and weight savings.


We chose to use Helical Valves on our 991 GT3 / GT3 RS track exhaust systems for their unprecedented quality - which have been proven by many OEM manufacturers such as McLaren, Ferrari, Lamborghini, and many more. Helical valves are an integral part of our Side Muffler Bypass pipes, opening and closing with precision to control the gas flow and optimising engine back-pressure for improved performance. Helical’s extensive experience in high-volume OEM automotive applications has led to standard features such as an extremely durable pneumatic actuator, precision flat sealing faces inside the valve, stiffening ribs and high-temperature bearings at both ends of the butterfly spindle.


  • Fits all Porsche 991 GT3 / GT3 RS vehicles (2014-2016)
  • Highest quality Helical valves
  • Includes O2 bungs for factory like functionality when paired with Fabspeed Long Tube Competition Headers
  • Saves 34 lbs from the rear of the vehicle
  • Replicates aggressive CUP car sound for the street
  • 14-16ga T304 Stainless Steel construction
  • Simple bolt-on installation
  • All Fabspeed performance products are backed by the Fabspeed Lifetime Limited Warranty

FABSPEED Motorsport

Exotic Car Performance Specialist

For over 20 years, Fabspeed has been engineering and manufacturing the world's finest stainless steel high performance exhaust systems and components, air intake products, ECU tuning, and more, specifically-tailored for high-end sports cars and exotics. From Porsche to McLaren, our expertise is unmatched and it shows in everything that we do. Our dyno-proven performance products provide an exhilarating driving experience and are backed by a Limited Lifetime Warranty.

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