Catalyst / Bypass

Fabspeed Catbypass Pipe Conversion Kit. 

The Fabspeed Porsche 993 Carrera Bypass Conversion Kit is a modular exhaust conversion package designed for 1994–1998 Porsche 993 Carrera models already equipped with a Fabspeed Cat Bypass X-Pipe.

Fits:

• Porsche 993 (911) C2 1994-97
• Porsche 993 (911) C4 1994-97
• Porsche 993 (911) C2S 1994-97
• Porsche 993 (911) C4S 1994-97  

Rather than replacing the complete Fabspeed X-pipe assembly, this kit allows the outlet sections to be changed.

This modular arrangement allows the exhaust configuration to be changed relatively quickly depending on the vehicle's intended use.

Fabspeed manufactures the conversion sections from CNC mandrel-bent T304L stainless steel and describes installation as a direct bolt-on process requiring no cutting or welding.

What This Product Does:
The conversion kit changes the exhaust outlet configuration downstream of the existing Fabspeed X-pipe.

It can either:

• Replace the catalyst sections with straight-through pipes
• Reduce exhaust restriction further
• Increase exhaust volume
• Produce a more aggressive race-oriented sound
• Reduce exhaust-system weight
• Maximise exhaust flow for track use

The main advantage is that an owner with the compatible Fabspeed X-pipe does not need to purchase an entirely different exhaust system to change.

Symptoms Of Wear Or Failure:
The conversion kit itself is primarily a performance and configuration upgrade, so it does not need routine replacement when functioning correctly.

However, catalyst sections, bypass pipes, joints and clamps can deteriorate through heat, vibration and age.

Possible symptoms include:

• Exhaust blowing or hissing
• Ticking noises from leaking joints
• Black soot around exhaust connections
• Loose or damaged clamps
• Exhaust sections moving excessively
• Metallic rattling
• Catalyst substrate rattling internally
• Reduced engine performance
• Increased exhaust restriction
• Poor high-RPM response
• Excessive heat around the catalyst
• Cracked welds
• Corroded pipework
• Damaged flanges
• Check Engine Light relating to catalyst efficiency
• Unusual exhaust smell
• Exhaust components sitting out of alignment

A Check Engine Light should always be diagnosed properly, as oxygen sensors and other engine-management faults can produce similar warnings.

Why Replacement Matters:
A damaged exhaust section can affect both performance and reliability.

Exhaust leaks may allow extremely hot gases to escape around nearby components, while a collapsed catalyst can restrict exhaust flow.

Continued use of damaged components may contribute to:
Reduced engine performance
Increased exhaust temperatures
Poor throttle response
Increased stress on adjoining exhaust components
Excessive exhaust noise
Catalyst-related fault codes
Further deterioration of clamps and joints

Replacing worn or damaged conversion sections restores secure exhaust routing and correct exhaust flow.

For a healthy existing Fabspeed X-pipe, however, this kit is primarily a configuration, performance and sound upgrade rather than a maintenance requirement.

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.

FSPOR993CBCK

The product you are viewing cross references to these numbers

Fabspeed RSR Header Muffler Bypass Straight Pipes 993 RSR Factory Race Car Style. 

The Fabspeed Porsche 993 Carrera RSR Header Muffler Bypass Straight Pipes are a performance exhaust upgrade designed to deliver an uncompromising motorsport-inspired exhaust note from the iconic air-cooled Porsche 911 Carrera (993).

Fits:

• Porsche 993 (911) C2 1994-97
• Porsche 993 (911) C4 1994-97  

Developed as an optional upgrade for the Fabspeed Maxflo RSR Header/Muffler Kit, these straight pipes replace the existing Fabspeed centre muffler or X-pipe, allowing exhaust gases to pass through a direct, minimally silenced exhaust path.

Inspired by the aggressive sound and lightweight exhaust arrangements associated with Porsche's factory 993 RSR racing cars, this upgrade is intended for drivers who want to experience a significantly louder and more visceral exhaust character.

Manufactured in-house by Fabspeed Motorsport from high-quality T304L stainless steel, the bypass pipes combine durable construction with a motorsport-focused design.

Unlike a conventional road exhaust system, which uses mufflers and resonators to reduce noise, these straight pipes remove the sound-reducing component from the compatible Fabspeed RSR exhaust arrangement.

The result is a dramatically louder, sharper and more aggressive exhaust note that emphasises the mechanical character of Porsche's naturally aspirated air-cooled flat-six engine.

The design also eliminates the weight associated with the existing muffler or X-pipe section, providing a lighter exhaust configuration.

The pipes connect directly to Fabspeed's RSR equal-length headers, including compatible header versions with or without cabin heating provisions.

Installation uses the existing aerospace-style V-band clamping arrangement, allowing the straight pipes to be exchanged for the compatible Fabspeed muffler or X-pipe without permanent modification to the headers.

Fabspeed also highlights the ability to return to a quieter exhaust configuration relatively quickly, making the system attractive to enthusiasts who alternate between circuit events and other permitted vehicle uses.

These bypass pipes are particularly suited to track-focused Porsche 993 Carrera builds, motorsport-inspired restorations and drivers seeking an authentic RSR-style exhaust experience.

What This Product Does:
The Fabspeed RSR Muffler Bypass Straight Pipes replace the muffler or X-pipe section of a compatible Fabspeed RSR exhaust system.

Their primary functions include:

• Bypass the Exhaust Muffler: Remove the sound-reducing centre section from the compatible Fabspeed Maxflo RSR system.
• Create an Aggressive RSR-Style Exhaust Note: Produce a significantly louder sound inspired by Porsche's air-cooled RSR racing cars.
• Provide a Direct Exhaust Flow Path: Allow exhaust gases to travel through straight stainless steel pipes rather than the existing muffler or X-pipe.
• Reduce Exhaust System Weight: Eliminate the mass of the removed centre muffler or X-pipe assembly.
• Complement Equal-Length RSR Headers: Connect directly to compatible Fabspeed RSR headers.
• Enhance the Motorsport Experience: Emphasise the natural exhaust character of the Porsche 993 Carrera flat-six engine.
• Support Track-Focused Configurations: Provide a lightweight, high-volume exhaust arrangement for suitable motorsport applications.
• Allow Reversible Configuration Changes: Use the existing V-band connection system to facilitate refitting the compatible muffler.
• Maintain Stainless Steel Durability: T304L construction provides resistance to corrosion and prolonged exhaust heat exposure.
• Preserve Compatible Fabspeed Fitment: Work with the intended RSR header and exhaust mounting arrangement.

Symptoms Of Wear Or Failure:
Unlike factory mechanical components that are generally replaced because they have worn out, the Fabspeed RSR Muffler Bypass Straight Pipes are primarily a performance and sound upgrade.

However, if an existing exhaust centre section is damaged, corroded or leaking, replacing or reconfiguring it may also form part of an exhaust repair.

Common signs of wear or failure in the existing exhaust assembly include:

• Cracks, failed connections or damaged pipework may allow exhaust gases to escape before reaching the intended outlet.
• Louder-than-normal exhaust noise.
• Ticking, hissing or blowing sounds.
• Soot deposits around pipe joints.
• Exhaust fumes near the vehicle.
• Increased noise under acceleration.
• Original or ageing exhaust components may corrode following prolonged exposure to moisture, road salt and heat cycles.
• Heavy external rust.
• Corroded welds or connections.
• Perforated exhaust sections.
• Weakening or splitting of metal components.
• Visible deterioration around mounting points.
• Vibration, impacts and repeated thermal expansion can contribute to exhaust component damage.
• Visible cracks.
• Abnormal exhaust noise.
• Loose or unsupported sections.
• Exhaust leakage under load.
• Rattling or vibration beneath the vehicle.
• V-band clamps and associated sealing interfaces must remain correctly positioned and secure.
• Exhaust leaks around the joints.
• Rattling near the connection points.
• Movement between exhaust sections.
• Soot marks around the mating flanges.
• Inconsistent exhaust alignment.
• Worn hangers or incorrectly installed components may allow excessive movement of the exhaust assembly.
• Metallic rattling.
• Contact with surrounding bodywork or heat shields.
• Increased vibration.
• Knocking during acceleration or over uneven surfaces.
• A damaged muffler or exhaust section may develop internal problems that affect gas flow.
• Reduced engine responsiveness.
• Unusual rattling from inside the muffler.
• Abnormal exhaust backpressure.
• Changes in exhaust sound.

Why Replacement / Upgrading Matters:
Installing the Fabspeed RSR Muffler Bypass Straight Pipes changes the character of the Porsche 993 Carrera exhaust system, with the primary benefits focused on sound, weight reduction and motorsport-inspired performance.

• Maximum Motorsport Sound: Creates a substantially louder exhaust note inspired by factory Porsche RSR racing cars.
• Direct Exhaust Flow: Replaces the muffled centre section with a straighter exhaust passage.
• Reduced Exhaust Weight: Removes the weight associated with the existing Fabspeed muffler or X-pipe.
• Aggressive Flat-Six Character: Makes the distinctive Porsche air-cooled engine sound more prominent.
• Track-Focused Configuration: Suitable for compatible vehicles prepared for appropriate motorsport environments.
• Stainless Steel Construction: Uses corrosion-resistant T304L stainless steel for durable exhaust service.
• Precision-Matched Fitment: Designed to attach to Fabspeed RSR equal-length headers.
• Compatible with Heated or Non-Heated Headers: Works with the relevant Fabspeed RSR header variants.
• Reversible Installation: Allows the Fabspeed muffler or X-pipe configuration to be restored using the compatible V-band system.
• No Permanent Header Modification: Uses the intended Fabspeed mounting connections.
• Motorsport-Inspired Styling and Engineering: Reflects the lightweight, high-volume exhaust concept associated with Porsche 993 RSR racing applications.
• Fabspeed Motorsport Development: Manufactured by a specialist in Porsche performance exhaust systems.

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.

Fabspeed Sport Cat Conversion Kit.

The Fabspeed Porsche 993 Carrera Sport Cat Conversion Kit is a modular exhaust conversion package designed for 1994–1998 Porsche 993 Carrera models already equipped with a Fabspeed Sport Cat X-Pipe.

Fits:

• Porsche 993 (911) C2 1994-97
• Porsche 993 (911) C4 1994-97
• Porsche 993 (911) C2S 1994-97
• Porsche 993 (911) C4S 1994-97  

Rather than replacing the complete Fabspeed X-pipe assembly, this kit allows the outlet sections to be changed.

This modular arrangement allows the exhaust configuration to be changed relatively quickly depending on the vehicle's intended use.

Fabspeed manufactures the conversion sections from CNC mandrel-bent T304L stainless steel and describes installation as a direct bolt-on process requiring no cutting or welding.

What This Product Does:
The conversion kit changes the exhaust outlet configuration downstream of the existing Fabspeed X-pipe.

It can either:

• Add high-flow catalytic converters
• Reduce exhaust restriction compared with conventional restrictive catalysts
• Maintain catalytic exhaust treatment
• Provide a stronger performance exhaust sound
• Retain a more refined configuration than straight bypass pipes

The main advantage is that an owner with the compatible Fabspeed X-pipe does not need to purchase an entirely different exhaust system to change.

Symptoms Of Wear Or Failure:
The conversion kit itself is primarily a performance and configuration upgrade, so it does not need routine replacement when functioning correctly.

However, catalyst sections, bypass pipes, joints and clamps can deteriorate through heat, vibration and age.

Possible symptoms include:

• Exhaust blowing or hissing
• Ticking noises from leaking joints
• Black soot around exhaust connections
• Loose or damaged clamps
• Exhaust sections moving excessively
• Metallic rattling
• Catalyst substrate rattling internally
• Reduced engine performance
• Increased exhaust restriction
• Poor high-RPM response
• Excessive heat around the catalyst
• Cracked welds
• Corroded pipework
• Damaged flanges
• Check Engine Light relating to catalyst efficiency
• Unusual exhaust smell
• Exhaust components sitting out of alignment

A Check Engine Light should always be diagnosed properly, as oxygen sensors and other engine-management faults can produce similar warnings.

Why Replacement Matters:
A damaged exhaust section can affect both performance and reliability.

Exhaust leaks may allow extremely hot gases to escape around nearby components, while a collapsed catalyst can restrict exhaust flow.

Continued use of damaged components may contribute to:
Reduced engine performance
Increased exhaust temperatures
Poor throttle response
Increased stress on adjoining exhaust components
Excessive exhaust noise
Catalyst-related fault codes
Further deterioration of clamps and joints

Replacing worn or damaged conversion sections restores secure exhaust routing and correct exhaust flow.

For a healthy existing Fabspeed X-pipe, however, this kit is primarily a configuration, performance and sound upgrade rather than a maintenance requirement.

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.

FSPOR993SCCK

The product you are viewing cross references to these numbers

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

The product you are viewing cross references to these numbers

Fabspeed Modular cat bypass x-pipe Competition ONLY.

Replaces the restrictive factory catalytic converters with much less restrictive straight-through pipes for maximum flow and performance.

FEATURES:

• Fits all Porsche 993 Turbo / Turbo S vehicles worldwide (1995-1998)
• Fabspeed's Primary Catbypass 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 12 lbs from the rear of the vehicle
• Adds an aggressive exhaust note for exotic high-performance sound
• Direct bolt-on replacement for the heavy factory catalytic converters on the 993 Turbo
• Constructed from polished T304L stainless steel
• Optional 02 spacers available to help prevent triggering the Check Engine Light
• All Fabspeed performance products are backed by the Fabspeed Lifetime Warranty

DISCLAIMER: This product removes the OEM intake filter system from the vehicle, and as such, is strictly intended for closed track events and off-road use only. This product contains a High-Flow Air Filter solely intended for track and race cars as it is NOT California Air Resources Board Certified (CARB) and not EPA certified. You are hereby informed and warned to check your local, state, and federal 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.

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, never to be driven on public roads. This product is or contains a Racing Cat Bypass Pipe, which will give you check engine lights on OBD2 cars. Racing Cat Bypass Pipes are solely intended for track and race cars as they are NOT California Air Resources Board Certified (CARB) and not EPA certified. You are hereby informed and warned to check your local, state, and federal 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.

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: 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.

FSPOR993TCBX

The product you are viewing cross references to these numbers