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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://www.design91.uk/images/schemaLogo.png https://www.design91.uk/images/schemaLogo.png +443456003478 https://www.design91.uk Facebook Instagram

Catalyst / Bypass

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DISPLAYING 1 to 3 (of 3 products)
CARP68NGTSS01_KIT
Product Information
Product Information
Sport exhaust system manifold-back with - catalytic bypass - Center silencer bypass Porsche 968

cargraphic

Fits for:
Porsche 968
Porsche 968 CS

Product description:
CARGRAPHIC N-GT Sport Exhaust System Manifold Back SS304L - Homologated for FIA N-GT class

Consisting of:
• CARGRAPHIC Downpipe with catalytic converter replacement pipe (empty catalytic housing), exhaust pipe / diameter: 2x Ø48mm > 1x Ø63,50mm
• CARGRAPHIC Center silencer replacement pipe, exhaust pipe / diameter: 1x Ø63,50mm > 2x Ø48mm
• CARGRAPHIC Sport rear silencer, exhaust pipe / diameter: 2x Ø48mm > 1x Ø63,50mm
• CARGRAPHIC Sport tailpipe Ø115x85mm oval, slash cut, rolled-in - Mirror polished

NO DRONE OR RESONATION even in combination with other CARGRAPHIC exhaust components fitted.

Features:

• Over 9kg weight saving compared to factory exhaust system
• Specially designed and homologated for N-GT class reglement
• All parts are interchangeable with factory / OE parts
• Absorptive silencer design with CNC mandrel-bent pipework
• Fully made from SS-304L lightweight stainless steel
• High performance components, dyno tested
• Reinforced laser-cut brackets
• Reduced backpressure due to freer flowing
• Reduced operating temperature
• Maximized performance
• Improved throttle response, freer revving
• Improved enhanced acoustics with no drone, resonation or vibration
• Model specific tuned sound still in keeping with the Marque
• Weight reduction

PERFORMANCE - Made in Germany

up to 11KW (15PS) more power and 15Nm additional torque
with optional CARGRAPHIC Motronic / DEM upgrade up to 26KW (35PS) more power and 35Nm additional torque!

Fitting Service:
Benefit from our fitting service in our modern and hightech workshop. A team of qualified, experienced technicians fulfill all your needs with due skill, care and diligence.

NOTE: In the United Kingdom, 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. They are not MOT compliant and cannot be used on public roads. These components are intended solely for race and track use.

For vehicles manufactured before 1st March 2001, a non-type approved sports catalytic converter may be fitted, provided it offers comparable performance to the original and the vehicle continues to meet the applicable emissions standards for its age. The vehicle must still pass an MOT test.

If you are located outside the UK, please check your local laws and regulations to ensure compliance.

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

CARP68NGTSS01_KIT
94411104111
94411108112
94411199111

The product you are viewing cross references to these numbers
CARP68NGTS01_KIT
Product Information
Product Information
Sport exhaust system manifold-back with - catalytic bypass for Porsche 968

cargraphic

Fits for:
Porsche 968
Porsche 968 CS

Product description:
CARGRAPHIC N-GT Sport Exhaust System Manifold Back SS304L - Homologated for FIA N-GT class

Consisting of:
• CARGRAPHIC Downpipe with catalytic converter replacement pipe (empty catalytic housing), exhaust pipe / diameter: 2x Ø48mm > 1x Ø63,50mm
• CARGRAPHIC Sport center silencer, exhaust pipe / diameter: 1x Ø63,50mm > 2x Ø48mm
• CARGRAPHIC Sport rear silencer, exhaust pipe / diameter: 2x Ø48mm > 1x Ø63,50mm
• CARGRAPHIC Sport tailpipe Ø115x85mm oval, slash cut, rolled-in - Mirror polished

NO DRONE OR RESONATION even in combination with other CARGRAPHIC exhaust components fitted.

Features:
• Over 9kg weight saving compared to factory exhaust system
• Specially designed and homologated for N-GT class reglement
• All parts are interchangeable with factory / OE parts
• Absorptive silencer design with CNC mandrel-bent pipework
• Fully made from SS-304L lightweight stainless steel
• High performance components, dyno tested
• Reinforced laser-cut brackets
• Reduced backpressure due to freer flowing
• Reduced operating temperature
• Maximized performance
• Improved throttle response, freer revving
• Improved enhanced acoustics with no drone, resonation or vibration
• Model specific tuned sound still in keeping with the Marque<
• Weight reduction

PERFORMANCE - Made in Germany

up to 11KW (15PS) more power and 15Nm additional torque
with optional CARGRAPHIC Motronic / DEM upgrade up to 26KW (35PS) more power and 35Nm additional torque!

Fitting Service:
Benefit from our fitting service in our modern and hightech workshop. A team of qualified, experienced technicians fulfill all your needs with due skill, care and diligence.

NOTE: In the United Kingdom, 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. They are not MOT compliant and cannot be used on public roads. These components are intended solely for race and track use.

For vehicles manufactured before 1st March 2001, a non-type approved sports catalytic converter may be fitted, provided it offers comparable performance to the original and the vehicle continues to meet the applicable emissions standards for its age. The vehicle must still pass an MOT test.

If you are located outside the UK, please check your local laws and regulations to ensure compliance.
CARP68NGT1KATER
Product Information
Product Information
Sport downpipe manifold-back with catalytic converter replacement pipe - Porsche 968 3.0L CARGRAPHIC N-GT

cargraphic

Fits for:
Porsche 968 3.0L
Porsche 968 CS 3.0L

Product description:
CARGRAPHIC N-GT Sport Downpipe Manifold Back SS304L - Homologated for N-GT class

Consisting of:
CARGRAPHIC Downpipe with catalytic converter replacement (BYPASS) with 2x48mm > 63,50mm pipework

NO DRONE OR RESONATION even in combination with other CARGRAPHIC exhaust components fitted.

Features:

• Specially designed and homologated for N-GT class reglement
• All parts are interchangeable with factory / OE parts
• Fully made from SS304L lightweight stainless steel
• High performance components, dyno tested
• Reinforced laser-cut brackets
• Reduced backpressure due to freer flowing
• Reduced operating temperature
• Maximized performance
• Improved throttle response, freer revving
• Improved enhanced acoustics with no drone, resonation or vibration
• Model specific tuned sound still in keeping with the Marque
• Weight reduction

PERFORMANCE - Made in Germany

up to 11KW (15PS) more power and 15Nm additional torque

NOTE: In the United Kingdom, 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. They are not MOT compliant and cannot be used on public roads. These components are intended solely for race and track use.

For vehicles manufactured before 1st March 2001, a non-type approved sports catalytic converter may be fitted, provided it offers comparable performance to the original and the vehicle continues to meet the applicable emissions standards for its age. The vehicle must still pass an MOT test.

If you are located outside the UK, please check your local laws and regulations to ensure compliance.

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

CARP68NGT1KATER
94411108112
94411199111

The product you are viewing cross references to these numbers
DISPLAYING 1 to 3 (of 3 products)
Also found on these pages
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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