Soul Performance Valved Side-Muffler Bypass Pipes for 991 Porsche 911 GT3 / GT3 RS / R

SOUL Performance Products’ Valved Side Muffler Bypass Pipes for the Porsche 991 GT3 / GT3 RS / 911R replace the bulky factory side mufflers with lightweight, free-flowing 3″ T304L stainless valved sections, shedding over 35 lb from the rear of the car while dramatically improving heat management around the engine bay and rear tires. Large 3″ mandrel-bent primaries and an enlarged opening into the secondary pipe increase flow and help equalize pressure in the factory center muffler, promoting its longevity under repeated hard use. High-quality valves and flex bellows are engineered to operate like OEM, giving you a smoother, more refined transition between quiet and loud than a center muffler bypass, moderately louder and more present with the valves closed, and a truly exotic, motorsport-inspired GT3 pitch when open. Each set is fabricated from 3″ .065″-wall T304L stainless with high-grade flex bellows for durability, then fixture-tested to ensure direct bolt-on fitment with no cutting or permanent modification required. Backed by SOUL Performance Products’ renowned Lifetime Warranty on both the valves and the piping, these Valved Side Muffler Bypass Pipes are an ideal solution for 991.1 / 991.2 GT3, GT3 RS, and 911R owners who want major weight savings, cooler temps, and a more exciting, controllable exhaust note that still works perfectly for daily use and track days alike.

Development & Testing

• By removing the side mufflers, significant weight savings are achieved, aiding in heat management within the engine bay and contributing to cooler rear tires. To ensure longevity, the hole leading into the secondary pipe is enlarged, equalizing pressure in the center muffler. Flex bellows are incorporated to facilitate straightforward installation and enhance durability, especially in demanding racing conditions, resembling the OEM standards. The implementation of large 3″ diameter primary piping promotes increased flow, while the high-quality valves operate like the factory specifications.

Construction

• Every set is meticulously crafted from mandrel-bent T304L stainless steel tubing with a 3″ diameter and .065″ wall thickness. Additionally, high-quality flex bellows are incorporated into each set to ensure exceptional durability and longevity.

Sound

• The sound transition between open and closed states is exceptionally smooth compared to a center muffler bypass setup. When the valves are closed, the tone experiences a moderate increase while maintaining a comfortable sound level when the factory center muffler is installed. On the other hand, when the valves are open, a refined and exotic pitch is revealed, perfectly complementing the high-performance nature of the GT3 engine.

Bolt On & Go

• To ensure flawless fitment, every exhaust undergoes rigorous testing in a fixture. Furthermore, each exhaust is meticulously foam packed for secure and protected shipping, arriving in perfect condition. The exhaust is designed for a straightforward installation, with no cutting or modifications required. It is ready to be installed seamlessly right out of the box.

Features

• Lightweight 3″ T304L stainless valved side bypass pipes
• Over 35lb rear-end weight reduction and improved heat management
• OEM-style valves and flex bellows for smooth, reliable operation
• Noticeably louder, more exotic GT3 tone with valves open, mild with valves closed
• Direct bolt-on fitment with no cutting, backed by SOUL’s Lifetime Warranty

Applications

• Porsche 911 GT3: 991.1, 991.2 (2013-2019)
  [3.8L F6] [4.0L F6]
  
• Porsche 911 GT3 RS: 991.1, 991.2 (2015-2019)
  [4.0L F6]
  
• Porsche 911 R: 991.1 (2016)
  [4.0L F6]
  

Notes

• Please note that this particular product does not possess CARB certification and may not comply with the legal requirements for use on emissions controlled vehicles. It is specifically intended for off-road use only.
• For compatibility with aftermarket headers that relocate the O2 bungs to the side-muffler bypass, optional O2 bungs can be added. However, as a default for the sake of weight reduction, Soul Performance Products does not include them. If you require this option, please get in touch with The Bulletproof Team for further assistance.

About SOUL Performance

SOUL Performance Products was founded by a group of automotive enthusiasts with deep industry experience and a commitment to doing right by their customers. Their mission is to deliver outstanding performance parts at fair pricing, backed by quality service and one of the best warranties in the industry. SOUL develops high-performance exhaust systems and components that are engineered for exceptional sound and proven performance, with products ready to ship quickly worldwide. Guided by core values of honesty, transparency, and passion for cars, they build strong community connections and prioritize customer satisfaction at every step. Operating out of a dedicated facility in Willow Grove, Pennsylvania, SOUL combines hands-on research, engineering, and manufacturing expertise to create parts that meet and exceed the demands of serious enthusiasts.