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Catalyst / Bypass

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DISPLAYING 1 to 10 (of 10 products)
EXHAUSTKIT23
Product Information
Product Information
Sports Exhaust VALVETROINC + X-Pipe Design Sports Cat bypass Package

designtek

DesignTek Valvetronic sports exhaust system gives smooth high torque feel to the wheels with the valves opened, +8HP/10 ft-lbs of torque to the wheels with the valves closed. Made from high quality 14-16 gauge T304 stainless steel, hydro-formed muffler cases, radiuses stressed relieved with 2000 degree ceramic fiber and stainless steel wool packed free flow mufflers.

Valvetronic
High-Performance Rear Exhaust with sound switch:
● Push the sound-button between:
Switch closed: Deep Sports Turbo Sound

Switch opened: Perfect Racing Sports Sound

DesignTek X-Pipe (primary muffler bypass) deletes the stock primary muffler and saves 6.4 lbs. from the rear of the vehicle. With a fast air flow the X-pipe increases BHP and Toque.

Made from high quality T304 14-16 gauge stainless steel, C.N.C. mandrel bent. The X-Pipe (primary muffler bypass) gives a great exotic car sound and power by about 5 decibels.

NOTE: Sports catalytic converters and bypass pipes do not have type approval and are not legally permitted for use on vehicles manufactured after 1st March 2001 in the United Kingdom. They are not MOT compliant and must not be used on public roads. These components are intended for race and track use only. If you are located outside the UK, please consult your local laws and regulations to ensure compliance.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

EXHAUSTKIT23
3606009719
3606009717
99711111330
99711122030
90091000303
N01024426

The product you are viewing cross references to these numbers
3010-11010
Product Information
Product Information
AWE Performance exhaust cross over pipes.

awe

Fits:
Porsche 997.2 (911) Carrera / S 3.6L - 3.8L

• Power Enhancement Bolt On
• P6.5lbs weight savings
• P5hp and 5 lb ft increase
• P100% T304 Stainless Steel Construction
• PPerfect Fitment - Guaranteed

For 2009-> 997.2 owners looking to eliminate the rear muffler, we offer Cross Over Pipe sections ...

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

3010-11010
3010-11010
3010

The product you are viewing cross references to these numbers
FSPOR9972GT3CRX
Product Information
Product Information
Fabspeed Exhaust cat-back competition race x-pipe.

fabspeed

The ultimate lightweight cat-back exhaust system for the 997.2 GT3 saves 54lbs (24.4kg) off the rear of the vehicle and is perfect for competitive track use, high performance drivers education events, or aggressive street sound.

FEATURES:

Fits all Porsche 997.2 GT3 / GT3 RS models (2010-2011)
• Perfect exhaust solution for maximum performance and sound during competitive track use, high performance drivers education events, or simply achieving an aggressive and exciting street sound.
• Saves over 54lbs (24kg) from the rear of the 997.2 GT3 which improves handling and acceleration by replacing the bulky factory center muffler and side mufflers
• Engineered and manufactured with 3" (76mm) T304L stainless steel tubing with integral tuned center X-Pipe to 70mm outlets.
• Bolt-on installation' no cutting or welding required
• Options of 4" Carbon Fiber Tips or 4" Stainless Steel Brushed Tips
• Includes two (2) 90 degree Turndown Tips for track use.
• All Fabspeed performance products are backed by Fabspeed's Limited Lifetime Warranty

NOTE: This is a straight pipe, racing oriented exhaust system built to be light and make power. As a result, the volume level will be very high inside the vehicle.

Please note: This is a special-order item manufactured to order. In some cases, please allow 4 – 5 weeks for the delivery. Special order items cannot be cancelled from this supplier once your order has been placed.

Please note: sports catalytic converters or bypass pipes do have type approval and may not be legally installed on vehicles manufactured after 1st March 2001. They can not be used on a public road and are not MOT compliant, they are designed for race and track cars only. 


Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

FSPOR9972GT3CRX
99711102792
99711102793
99711102797
99711102780
99711102799
99711104794
99711104797
99711104782
99711104784
99711104894
99711104897
99711104882
99711104884
99711104798
99711104785
99711104898
99711104885

The product you are viewing cross references to these numbers
FSPOR9972GT3CMB
Product Information
Product Information
Exhaust Centre Muffler Bypass Pipe

fabspeed

Direct replacement for the failure-prone OEM muffler providing improved flow, weight savings, and aggressive sound. Our new talk-pipe design blends the exhaust from the right and left cylinders creating an incredible smooth blended sound, and our simplified two-bolt mounting system makes installing easier than ever!

FEATURES:

Fits all Porsche 997.2 GT3 / GT3 RS vehicles (2010-2012)
• Adds 10 whp and 6 ft-lbs of torque increasing throttle response
• Saves 10 lbs from the rear of the vehicle
• Retains Sport Mode control button when used with factory side mufflers
• 14-16ga T304 Stainless Steel construction
• Includes 4" Deluxe Dual Style Tips in your choice of Carbon Fiber, Polished Stainless or Satin Black, or you can opt to use your OEM tips
• All Fabspeed performance products are backed by the Fabspeed Lifetime Limited Warranty

Please note: This is a special-order item manufactured to order. In some cases, please allow 4 – 5 weeks for the delivery. Special order items cannot be cancelled from this supplier once your order has been placed.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

FSPOR9972GT3CMB
99711102792
99711102793
99711102797
99711102780
99711102799

The product you are viewing cross references to these numbers
3606309706
Product Information
Product Information
DesignTek Headers Cat Bybass

designtek

Fits:
Porsche 997 GT3 / GT3RS 2007>>

High quality T304 Stainless steel equal length headers C.N.C. mandrel bent, computer numerical controlled mandrel bending equipment. The headers come complete with the provision for the before and after lambda sensors. As the vehicle will not be using the reading from these sensors the ECU will need to be re-programmed or re-mapped.
The Designtek are designed for maximum flow with no restriction. The headers are designed to produce more torque and horsepower across the Rev range. This products is designed for track cars and highly tuned vehicles

NOTE: Sports catalytic converters and bypass pipes do not have type approval and are not legally permitted for use on vehicles manufactured after 1st March 2001 in the United Kingdom. They are not MOT compliant and must not be used on public roads. These components are intended for race and track use only. If you are located outside the UK, please consult your local laws and regulations to ensure compliance.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

3606309706
99711302191
997113021AX
99711302291
997113022AX
99711302194
997113021BX
99711302197
997113021CX
99711302294
997113022BX
99711302297
997113022CX

The product you are viewing cross references to these numbers
3606109978/1
Product Information
Product Information
Exhaust manifold with 200 cell catalytic converter. Porsche 997.2


designtek

Fits:
Porsche 997.2 Carrera 2009-12

Made out of 304 grade stainless steel. You may need lambda extensions if your car has engine check light on after installation.

Please note: These sport cats will make your car sound louder than with stock cats. If you have ,or intend to install sport silencers, you may find the car is a bit loo loud. We recommend to use one sport exhaust component if you are concerned about decibel levels.

NOTE: Sports catalytic converters and bypass pipes do not have type approval and are not legally permitted for use on vehicles manufactured after 1st March 2001 in the United Kingdom. They are not MOT compliant and must not be used on public roads. These components are intended for race and track use only. If you are located outside the UK, please consult your local laws and regulations to ensure compliance.



Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

3606109978
99711310932
997113109AX
99711311032
997113110AX

The product you are viewing cross references to these numbers
3606109975
Product Information
Product Information
Exhaust manifold with cat bypass. These headers are offroad use only. 
These manifolds have an empty chamber that gives an impression you have catalytic converters on the car.


designtek

Fits:
Porsche 997.2 Carrera 2009-12

Made out of 304 grade stainless steel and would provide gains of 15 BHP. Remapping of the car after fitment is highly recomended.

Please note: These sport cats will make your car sound louder than with stock cats. If you have ,or intend to install sport silencers, you may find the car is a bit loo loud. We recommend to use one sport exhaust component if you are concerned about decibel levels.

NOTE: Sports catalytic converters and bypass pipes do not have type approval and are not legally permitted for use on vehicles manufactured after 1st March 2001 in the United Kingdom. They are not MOT compliant and must not be used on public roads. These components are intended for race and track use only. If you are located outside the UK, please consult your local laws and regulations to ensure compliance.



Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

3606109975
99711310932
997113109AX
99711311032
997113110AX

The product you are viewing cross references to these numbers
3606109978
Product Information
Product Information
Exhaust manifold with cat bypass. These headers are offroad use only.

designtek

Fits:
Porsche 997.2 Carrera 2009-12

Made out of 304 grade stainless steel and would provide gains of 15 BHP. Remapping of the car after fitment is highly recomended.

Please note: These sport cats will make your car sound louder than with stock cats. If you have ,or intend to install sport silencers, you may find the car is a bit loo loud. We recommend to use one sport exhaust component if you are concerned about decibel levels.

NOTE: Sports catalytic converters and bypass pipes do not have type approval and are not legally permitted for use on vehicles manufactured after 1st March 2001 in the United Kingdom. They are not MOT compliant and must not be used on public roads. These components are intended for race and track use only. If you are located outside the UK, please consult your local laws and regulations to ensure compliance.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

3606109978
99711310932
997113109AX
99711311032
997113110AX

The product you are viewing cross references to these numbers
100390100392
Product Information
Product Information
Lambda Sensor Blanking Plug and Receiver Socket Set.
In case you need to relocate your existing lambda probe because it's not in the right location. Welding and cutting specialist required.


Fits:
Many Porsche vehicles. Universal kit.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

100390100392
100390
100392

The product you are viewing cross references to these numbers
3606609717
Product Information
Product Information
DesignTek Sport Center Section for 997GT3, 997GT3 RS and GT3 Cup cars - Stainless Steel Polished with Matt Black pipes

designtek

This sports centre sections is a direct bolt on replacement, you don't even need to removal of bumper, Proprietary megaphone design- mandrel bent tubing which saves 14 lbs over the stock center section ( GT3 , RS with Ti center muffler saves 5 lbs )
Sport button remains fully functional for every day use, absolutely NO modifications. This system offers a deep aggressive exhaust note over the Porsche stock system the factory primary mufflers, catalyst and exhaust flaps are all retained

The DesignTek Sport Center Section system is a direct bolt on replacement center section which reduces weight, improves sound and offers a mild increase in performance. Porsche has done a wonderful job with the design and manufacture of the factory system with virtually no improvement to be made by installing a complete (mufflers, headers and cats) aftermarket system.

Direct bolt on replacement center section with dual 3.5 stainless tips (factory offers dual 3"). The system is made of mandrel bent T304 stainless tubing which is TIG welded and features a proprietary megaphone design to improve sound in the upper RPM range. The system saves over 14 lbs of weight over the stock ( stock gt3) and (5 lbs over GT3RS with Ti muffler), power is up 3-5 hp on average and now the sound is finally worthy of this magnificent engine.

Fits:
Porsche 997 GT3 / GT3RS 2007>>

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

3606609717
99711102790
99711102792
99711102793
99711102797
99711102780
99711102799
55-PS115
126255

The product you are viewing cross references to these numbers
DISPLAYING 1 to 10 (of 10 products)
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About Catalyst / Bypass

Exhaust Catalytic Converters & Bypass Pipes – Performance, Efficiency & Flow Control

The catalytic converter plays a crucial role in your Porsche’s exhaust system, reducing harmful emissions while maintaining optimal exhaust flow. Positioned between the exhaust manifold and silencer, it converts toxic gases such as carbon monoxide, hydrocarbons, and nitrogen oxides into less harmful emissions before they exit the tailpipe.

At Design911, we offer a complete range of catalytic converters and bypass pipes for Porsche vehicles. Our manufacturer-quality converters ensure reliable emission control and long-term performance, while our bypass options are designed for track or performance use, optimising exhaust flow for maximum power and throttle response.

Whether you’re maintaining your Porsche to meet emissions standards or upgrading for improved exhaust performance, our selection includes both direct-fit converters and performance bypass kits built from high-grade stainless steel for strength, corrosion resistance, and durability.

What Do Catalytic Converters & Bypass Pipes Do?

A catalytic converter uses a fine mesh of precious metals to trigger chemical reactions that break down pollutants. The bypass alternative eliminates restriction in the exhaust flow, improving performance in non-emissions-controlled environments such as track driving.

Core Functions:

  • Converts toxic exhaust gases into environmentally friendly emissions.
  • Maintains exhaust back pressure for engine efficiency.
  • Reduces harmful NOx, CO, and HC emissions.
  • Supports smoother engine performance and throttle control.
  • Bypass versions enhance exhaust flow and improve power output for track cars.

Upgrading to a performance-grade system ensures your Porsche continues to meet emission requirements — or achieves greater flow and responsiveness for motorsport applications.

Why Do Catalytic Converters Fail?

Catalytic converters are exposed to extreme heat, unburnt fuel, and contaminants — all of which can degrade their performance over time.

Common Causes of Failure Include:

  • Carbon or oil buildup blocking the internal honeycomb.
  • Thermal damage from overheating or rich fuel mixtures.
  • Physical damage from road debris or misfiring engines.
  • Corrosion due to moisture and exhaust condensation.
  • Age-related wear reducing catalytic efficiency.

A failing converter can cause reduced engine power, poor fuel economy, rattling sounds, or a check-engine light. Replacing it restores emissions compliance, performance, and exhaust efficiency.

Why Replace or Upgrade with Precision-Engineered Components?

Replacing a failing converter or upgrading to a bypass pipe ensures your Porsche maintains peak performance and reliability.

Key Benefits:

  • Restores optimal emissions performance and efficiency.
  • Improves exhaust flow and throttle response.
  • Reduces engine stress and fuel consumption.
  • Durable stainless-steel construction for longevity.
  • Direct-fit compatibility for Porsche 911, Cayman, Boxster, Panamera, Macan and more.
  • Performance bypass options available for track and tuning applications.

Whether you want emissions compliance or maximum flow for competition use, our parts deliver reliability, precision, and performance.

Highlights:

  • Direct-fit catalytic converters and bypass pipes for Porsche models.
  • Precision-engineered for optimal flow and reduced emissions.
  • Built from heat-resistant stainless steel for durability.
  • Bypass pipes for performance tuning and track applications.
  • Restores power, efficiency, and exhaust sound balance.
  • Available for classic and modern Porsche vehicles.

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