SKU: 38356207353

Fabspeed 991.2 GT3/GT3 RS Side Muffler Bypass Pipes (17+) (FS.POR.9912GT3.SMB)

Sale price$616.93 Regular price$685.48
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Ships within 48 hours · Estimated delivery Jul 18 - Jul 23

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Description

Fabspeed 991.2 GT3/GT3 RS Side Muffler Bypass Pipes (17+) (FS.POR.9912GT3.SMB)Optimized design that replaces the heavy and restrictive factory GT3 side mufflers for improved exhaust flow, increased dynamic sports car sound and huge significant weight savings. Utilizing super premium Helical U. K. Aerospace grade valves along with the addition of O2 bungs, Fabspeed's Side Muffler Bypass Pipesprovide the ultimate street and track solution for the 991. 2 GT3 GT3 RS. Prefect upgrade for any Street Driven GT3 touring, GT3RS, Gt3 PDK

Optimized design that replaces the heavy and restrictive factory GT3 side mufflers for improved exhaust flow, increased dynamic sports car sound and huge significant weight savings.

Utilizing super premium Helical U.K. Aerospace grade valves along with the addition of O2 bungs, Fabspeed's Side Muffler Bypass Pipesprovide the ultimate street and track solution for the 991.2 GT3 / GT3 RS. Prefect upgrade for any Street Driven GT3 touring, GT3RS, Gt3 PDK cars. Factory Sport Button PSE is 100% retained with Fabspeed GT3 side muffler bypass pipes with exhaust valves.

FEATURES:

  • Fits all Porsche 991.2 GT3 / GT3 RSvehicles worldwide
  • Highest quality OEM Porsche Ag. Helical Limited United Kingdom exhaust valves are used for bullet-proof reliability.
  • Includes O2 bungs and plugs at no extra charge.
  • Saves 41 lbs 18.6 kg from the rear of the vehicle
  • CAT-BACK Emissions legal. Bolts onto OEM Porsche catalytic converters
  • Replicates aggressive CUP car sound for the street.
  • 14-16ga T304 Stainless Steel construction
  • Retains Sport Button PSE functionality.
  • Simple bolt-on installation- remove rear left and Right side mufflers and install these Works of Art..
  • All Fabspeed performance products are backed by the Fabspeed Lifetime Warranty

HELICAL VALVES:

We chose to use Helical Valves on our 991.2 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 optimizing 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 Ultra high temperature high-temperature bearings at both ends of the butterfly spindle. Helical is an Aerospace Company that also makes exhaust components. Fabspeed Motorsport USA is the USAs exclusive importer buyer.

O2 BUNGS:

We relocated the O2 bungs from the collector of the headers to the Side Muffler Bypass Pipes in order to maintain factory-like functionality with our Long Tube Competition Race Headers - allowing them to read all cylinders while maximizing the performance of the collector.This design will replace our existing SMBP's allowing you to upgrade to our Long Tube Race Header design at any time in the future. Extra oxygen sensor ports also allow Data Acquisition at any time. Another value added feature only from Fabspeed.

ClickHere For Install Instructions forPorsche Homelink Connection For Valvetronic Exhaust Control

Note: only Fabspeed Motorsport USA uses Helical Limited England exhaust valves on all systems. Porsche uses Helical exhaust valves on their GT3 mufflers because the valves are bullet-proof silica carbide. FYI- Ferrari, Lamborghini, McLaren, Aston Martin all demand and use Helical Exhaust Valves UK. for their sports cars and hypercars because only Helical doesn't melt, crack, break, flutter or rattle.

 

Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 38356207353

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Reviewed in the United States on April 18, 2026
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I recently had an opportunity to work on an old Troy-Bilt Snow Blower with a Carlisle Stud Bias Tire - 4.80-8 4 that had a continual leak and would not hold pressure for more than a day. After investigation, I discovered that it "Champagne" sized bubbles coming from an area on the sidewall that I circled in yellow "China" marker. Because of the size of the tire, I decided to purchase the "TireJect Mountain Bike (MTB) Tire Sealant Kit because I didn't require a lot of material to seal the tire. The TireJect Mountain Bike (MTB) Tire Sealant Kit came with an single 8oz container and I used 4 of those 8oz's in this single tire. The TireJect material sealed up the area beautifully. After the sealant cured, I was able to pump up the tire to 15PSI and it has held it's pressure for more than a week now. You can see from the photos, that the sidewalls in that yellow circled area were actually cracked (probably due to the tire sitting flat for more than a year). I highly recommend this product over previous products I have used in the past (Slime).
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