Fabspeed Rennsport Muffler System for 991.1 Porsche 911 GT3 & GT3 RS
As many GT3 owners are aware, the OEM mufflers are prone to cracking, breaking, and blowing out, especially the titanium mufflers on GT3RS models. Fabspeed set out to design a muffler replacement that addresses these issues while improving on the OEM design. Drawing on over 25 years of experience with both air- and water-cooled engines, Fabspeed increased the valve open tubing to 2.75 inches (70mm), which is the optimal diameter for GT3 engines to ensure low restriction, high velocity, and a high-pitched GT3 sound reminiscent of the GT3 CUP car. Additionally, Fabspeed incorporated their signature investment-cast X-pipe for optimal exhaust scavenging, merging the two cylinder banks without restricting exhaust flow. To maintain the factory muffler’s exhaust note and eliminate drone, Fabspeed replicated Porsche’s 7-chamber design, resulting in a completely drone-free system, even when paired with race headers. When combined with Fabspeed’s Side Muffler Muffler Bypass Pipes, this exhaust system delivers the ultimate emissions-compliant GT3 exhaust. This muffler is guaranteed to never break or fail.
Sound
- This muffler produces a tone similar to the OEM muffler, but with a slightly louder sound when the PSE is turned on. It also delivers a smoother, higher-pitched tone, enhanced by Fabspeed’s signature X-pipe.
Power
- On Fabspeed’s 991.1 GT3RS test car, when paired with the Side Muffler Bypass Pipes, the Rennsport Muffler delivered an impressive increase of 27ft/lbs of torque at 3,200rpm. From 2,900rpm to 5,700rpm, it gained 10 whp or more, with peak whp rising from 446 to 454. This results in an 8whp or 9hp gain at the crank.
Features
- Constructed from CNC cut T304L stainless steel
- Designed from 3D scans of the OEM muffler to achieve perfect bolt-on fitment
- Incorporates our signature cast X-pipe for superior flow and exhaust scavenging
- Paired with Side Muffler Bypass Pipes this muffler adds +27ft/lbs and +16whp
- Completely retains PSE valved exhaust functionality
- This cat-back system is emissions legal in all 50 states and the rest of the world
- Built in house at Fabspeed Motorsport USA in Fort Washington, PA
- Simple bolt-on installation, no cutting or welding required
- No CEL (check engine light) guaranteed
- All Fabspeed performance products are backed by the Fabspeed lifetime warranty
Applications
- Porsche 911 GT3: 991.1 (2014-2016) [4.0L F6]
- Porsche 911 GT3 RS: 991.1 (2015-2016) [4.0L F6]
Notes
- All Fabspeed products are expected to ship within one week of order, though timelines are often much quicker
- Exhaust system is designed to reuse OEM gaskets and hardware
About Fabspeed
Fabspeed Motorsport is situated in Fort Washington, Pennsylvania, within the United States of America. Their extensive 26,000 sqft. facility serves as a hub for various car clubs, including Porsche Club of America, Ferrari, McLaren, Lamborghini, and more. The company is renowned for its comprehensive approach to product development. They handle the entire process, from design and engineering to dyno testing, street trials, and racing assessments, ensuring the quality and performance of every item. Fabspeed also collaborates closely with race engine builders and tuners hailing from Italy, Germany, and the United States, resulting in the creation of the Ultimate Performance parts. To cater to their passionate global audience, Fabspeed meticulously crafts systems using aerospace-grade austenitic stainless steel, titanium, and carbon fiber materials, setting a standard for excellence in the industry.
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