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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 7 (of 7 products)
L-PO991T/2
Product Information
Product Information
The next step from Akrapovič for the Porsche 911 Turbo / Turbo S is the optional titanium link pipe set without cats, perfectly finished with a coating to offer greater durability without altering the look. Designed to create the best exhaust flow and offering a huge weight saving over stock—when used in conjunction with the Slip-On—the link pipes increase power and give the car a sporty racing sound. Enhancing the tuning opportunities of this superb car, the link pipes without cats are an easy-to-install performance upgrade.

Fits:
Porsche 991 (911) Turbo/Turbo S 2014>>

TECHNICAL DATA
** measured with: Porsche 911 Turbo/Turbo S (991) 2014

Maximum power:
- kW: plus 7.1 / 5400 rpm
- HP (m): plus 9.7 / 5400 rpm
- HP (i): plus 9.6 / 5400 rpm

Maximum torque:
- Nm: plus 50.0 / 2300 rpm
- lb-ft: plus 36.9 / 2300 rpm

Weight:
- minus 5.6 kg / 12.4 lb

Please note: When installing Akrapovič aftermarket optional link pipes without catalytic converters, which are developed for use on closed tracks only, remapping the ECU is mandatory. Akrapovic Delete-R will not eliminate possible engine check errors codes caused by increasing emissions flow.

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Related, superseded, cross reference or alternative numbers for comparison.

L-PO991T
99711300930
997113009AX
99711301030
997113010AX

The product you are viewing cross references to these numbers
Special Offer
3606109916
Product Information
Product Information
Exhaust cat bypass pipes with gaskets.

designtek

Fits:
Porsche 991.1 Turbo / Turbo S

Porsche 991.2 Turbo / Turbo S

Free-flowing straight pipes replace the bulky & restrictive factory catalytic converters; designed specifically for maximum flow during racing or competition.

FEATURES:
• Maximizes power and throttle response while decreasing back pressure.
• Completely removes the catalytic converters for maximum exhaust flow and performance.
• Constructed from high-quality stainless steel for optimum flow and maximum durability.
• Direct replacement bolt-on for stock cat or Sport Cats

DISCLAIMER: This product removes the OEM catalytic converters from the vehicle, and as such, is strictly intended for closed track events and off-road use only. This product is or contains a Racing Cat Bypass Pipe, which will give you check engine lights on OBD2 cars. We suggest pairing this product with racing software to prevent fault codes and check engine lights. Racing Cat Bypass Pipes are solely intended for track and race cars as they are NOT California Air Resources Board Certified and not EPA certified. You are hereby informed and warned to check your local, state, and federals laws before buying and installing these or any aftermarket parts to be sure whether usage is in violation. All installation-risk and use-risk is borne by the end-user and installer of these parts.

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.

3606109916
99711301030
99711300930
997113010AX
997113009AX

The product you are viewing cross references to these numbers
FSPOR991TCB
Product Information
Product Information
Fabspeed Exhaust Cat bypass Pipes.

fabspeed

Increase exhaust flow from the headers to the mufflers and improving power and sound by removing the bulky and restrictive factory catalytic converter.

FEATURES:
Fits all 991 Turbo vehicles (2013+)
• Fabspeed's Cat bypass Pipes replace the restrictive factory catalytic converters with much less restrictive straight-through pipes for maximum flow and performance
• Noticeable increase in power and improved throttle response
• Saves 10 lbs in the rear of the vehicle versus the bulky factory catalytic converters
• Adds aggressive exhaust note for high performance sound
• Constructed from high-quality 14-16 gauge C.N.C. mandrel-bent T304L stainless steel for optimum flow and maximum durability
• Direct bolt-on replacement
• 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.

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.

FSPOR991TCB
99711300930
997113009AX
99711301030
997113010AX

The product you are viewing cross references to these numbers
FSPOR991TSC
Product Information
Product Information
Fabspeed Exhaust Sport Catalytic Converters.

fabspeed

High-flowing, direct bolt-on replacement for the bulky & restrictive factory catalytic converters.

FEATURES:
Fits all 991 Turbo vehicles (2013+)
• Improves power and throttle response while decreasing back pressure
• High flow sport race cat for maximum flow and power.
• Constructed from high-quality 14-16 gauge T304L stainless steel for optimum flow and maximum durability
• Includes integrated O2 sensor bung for fuel-injected cars
• Direct replacement bolt-on for stock cat or cat bypass pipe

NOTE: Fabspeed's 200-cell high-flow catalytic converters are not C.A.R.B. certified and are for Off-Road Use ONLY in the state of California

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.

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.

FSPOR991TSC
99711300930
997113009AX
99711301030
997113010AX

The product you are viewing cross references to these numbers
Special Offer
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
TSPO991T13.403.ANK
Product Information
Product Information
Sports exhaust catalytic converter delete pipes Porsche 911 turbo and 911 turbo S 2013-2019
Fits both 991.1 and 991.2

tubi

Fits 2013-2019
Porsche 911 turbo 991.1
Porsche 911 turbo S 991.1
Porsche 911 turbo 991.2
Porsche 911 turbo S 991.2


RACETRACK USE ONLY
These components are designed and developed for racetrack use and to maximise the car's performance. They are not street legal and must be installed by professionals in the sector.

CATALYTIC CONVERTER REMOVAL
Complete removal of the catalytic converter minimises exhaust back pressure and delivers optimum results in terms of performance and weight reduction.

ECU REMAPPING - ENGINE LIGHT
Replacement or removal of components such as catalytic converters, GPFs and electric actuators may cause the engine warning light to come on. In this case, the installer must reprogram the software to eliminate the light.

MATERIAL
AISI 304 STAINLESS STEEL
A choice stainless steel ideal for aggressive environments where combustion emissions can cause serious chemical corrosion on other types of metal.

MAIN PIPE DIMENSION - 65mm
This is the diameter of the main pipe of the exhaust system.

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.
TSPO991T13.303.AK
Product Information
Product Information
Sports exhaust catalytic converter cell reduction pipe Porsche 911 turbo and 911 turbo S 2013-2019

tubi

Fits
Porsche 911 turbo 991.1
Porsche 911 turbo S 991.1
Porsche 911 turbo 991.2
Porsche 911 turbo S 991.2
2013-2019

RACETRACK USE ONLY
These components are designed and developed for racetrack use and to maximise the car's performance.
They are not street legal and must be installed by professionals in the sector

CATALYTIC CONVERTER REDUCED TO 200 CELLS
Race catalytic converters have fewer cells than standard factory systems. This reduces exhaust back pressure while still maintaining the operation of the catalytic converter, and improves performance and sound

ECU REMAPPING - FOR PERFORMANCE
On turbo cars, catalytic converter replacement may modify turbocharger operating conditions and cause a deterioration of the torque delivery curve. To ensure full benefit from the new racing component, the engine's ECU must be reprogrammed to maximise performance. If the engine warning light comes on, the ECU must always be reprogrammed to eliminate it

MATERIAL
AISI 304 STAINLESS STEEL
A choice stainless steel ideal for aggressive environments where combustion emissions can cause serious chemical corrosion on other types of metal

MAIN PIPE DIMENSION - 65mm
This is the diameter of the main pipe of the exhaust system

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.
DISPLAYING 1 to 7 (of 7 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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