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Design 911 Design 911 supply Porsche parts, Porsche spares and Porsche accessories, to both retail and to the trade. Our Porsche product and accessory range includes brakes, exhausts, tyres, wheels and Porsche panels and interiors. https://design91.uk/images/schemaLogo.png https://design91.uk/images/schemaLogo.png +443456003478 https://design91.uk Facebook Instagram

Catalyst / Bypass

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DISPLAYING 1 to 6 (of 6 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Related, superseded, cross reference or alternative numbers for comparison.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
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
DISPLAYING 1 to 6 (of 6 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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