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Sport Silencers / Mufflers
Filter by brand
Vehicle Group
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
Information
Fabspeed Muffler Bypass Pipe with Adjustable Turndown
Reduce weight, increase power, and improve sound with bypass pipes for both the primary and secondary mufflers; includes adjustable turndown tip for exhaust volume control.
FEATURES:
• Fits: Porsche 911 3.0L / Carrera 3.2L 1974-83 all models
• Very aggressive CUP car sound. Recommended for Track Use ONLY!
• Adds 14whp and significant throttle response
• Constructed from 14-16 gauge, T304 C.N.C. Mandrel bent stainless steel
• Saves 25 lbs from the vehicle
• Direct replacement for OEM muffler works with stock cats and fabspeed's catbypass pipes
• Easy on and easy off installation, perfect for weekend Track Events
• System comes with outlet pipe, clamp and slip-on turndown
• 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Related, superseded, cross reference or alternative numbers for comparison.
FSPOR911MB
The product you are viewing cross references to these numbers
Reduce weight, increase power, and improve sound with bypass pipes for both the primary and secondary mufflers; includes adjustable turndown tip for exhaust volume control.
FEATURES:
• Fits: Porsche 911 3.0L / Carrera 3.2L 1974-83 all models
• Very aggressive CUP car sound. Recommended for Track Use ONLY!
• Adds 14whp and significant throttle response
• Constructed from 14-16 gauge, T304 C.N.C. Mandrel bent stainless steel
• Saves 25 lbs from the vehicle
• Direct replacement for OEM muffler works with stock cats and fabspeed's catbypass pipes
• Easy on and easy off installation, perfect for weekend Track Events
• System comes with outlet pipe, clamp and slip-on turndown
• 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Related, superseded, cross reference or alternative numbers for comparison.
FSPOR911MB
91122091102
93011102200
93011102203
93011104300
93011104301
The product you are viewing cross references to these numbers
£296.00
Now £266.40
In stock
Vehicle Group
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
Information
DesignTek Sport Exhaust muffler / silencer rear box, with valves
with dual center outlet pipes "GT3" style
The DesignTek 'GT3 style' sports exhaust muffler with valves is a performance-focused upgrade designed for classic Porsche 911 models from 1975 to 1989. Combining modern exhaust technology with iconic GT3-inspired styling, this rear silencer enhances both the sound and driving experience of air-cooled 911s.
Fits:
Porsche 911 1975 - 1989
Please note: This system does not come with valve control system. You can add it to the basket afterwards.
This exhaust system features an integrated valve-controlled design, allowing you to switch between a more refined tone and a louder, more aggressive sports exhaust note. When open, the system delivers a deeper, freer-flowing sound with reduced backpressure, while the closed setting provides a more controlled, road-friendly exhaust tone.
Constructed using high-quality materials and precision engineering, this DesignTek muffler is built to withstand the high temperatures and demands of air-cooled engines. Its free-flowing internal design improves exhaust gas evacuation, which can contribute to improved engine responsiveness and efficiency. Performance exhaust systems like this are designed to reduce restriction and enhance airflow, helping engines breathe more effectively.
The GT3-style design brings a modern motorsport-inspired appearance to classic 911 models, typically featuring a more aggressive rear-end look compared to standard silencers. Designed as a direct-fit upgrade, it integrates with existing exhaust components for straightforward installation.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
3606001103
The product you are viewing cross references to these numbers
with dual center outlet pipes "GT3" style
The DesignTek 'GT3 style' sports exhaust muffler with valves is a performance-focused upgrade designed for classic Porsche 911 models from 1975 to 1989. Combining modern exhaust technology with iconic GT3-inspired styling, this rear silencer enhances both the sound and driving experience of air-cooled 911s.
Fits:
Porsche 911 1975 - 1989
Please note: This system does not come with valve control system. You can add it to the basket afterwards.
This exhaust system features an integrated valve-controlled design, allowing you to switch between a more refined tone and a louder, more aggressive sports exhaust note. When open, the system delivers a deeper, freer-flowing sound with reduced backpressure, while the closed setting provides a more controlled, road-friendly exhaust tone.
Constructed using high-quality materials and precision engineering, this DesignTek muffler is built to withstand the high temperatures and demands of air-cooled engines. Its free-flowing internal design improves exhaust gas evacuation, which can contribute to improved engine responsiveness and efficiency. Performance exhaust systems like this are designed to reduce restriction and enhance airflow, helping engines breathe more effectively.
The GT3-style design brings a modern motorsport-inspired appearance to classic 911 models, typically featuring a more aggressive rear-end look compared to standard silencers. Designed as a direct-fit upgrade, it integrates with existing exhaust components for straightforward installation.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
3606001103
93011102200
93011102203
93011104300
93011104301
93011104303
The product you are viewing cross references to these numbers
£1,500.00
Now £1,350.00
Arriving soon
Vehicle Group
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
Information
DesignTek Sport Exhaust muffler / silencer rear box, with valves, 1 IN 1 OUT
* with tail pipes
The DesignTek 1 IN 1 OUT sports exhaust muffler with valves is a performance-focused upgrade designed for classic Porsche 911 models from 1975 to 1989. Combining modern exhaust technology with the character of air-cooled flat-six engines, this rear silencer enhances sound, responsiveness, and overall driving experience while maintaining a clean, original-style single outlet appearance.
Fits:
Porsche 911 1975 - 1989
Please note: This system does not come with valve control system. You can add it to the basket afterwards.
Featuring a valve-controlled system, this exhaust allows you to switch between a refined, quieter tone for everyday driving and a more aggressive, free-flowing sports sound when desired. This dual-mode functionality gives you the flexibility to enjoy both comfort and performance in one system.
The 1 IN 1 OUT configuration retains a classic factory-style look while improving exhaust efficiency. The freer-flowing internal design helps reduce backpressure, supporting improved engine breathing and throttle response. Performance exhaust systems are widely used to enhance both sound and engine efficiency, delivering a more engaging driving experience.
Manufactured using high-quality materials and precision engineering, this DesignTek muffler is built to withstand the high temperatures and demands of air-cooled engines. Designed as a direct-fit replacement, it integrates with existing exhaust components for straightforward installation and reliable fitment. DesignTek exhaust systems are known for combining performance gains, durability, and easy installation, making them a popular upgrade choice.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
3606001105
The product you are viewing cross references to these numbers
* with tail pipes
The DesignTek 1 IN 1 OUT sports exhaust muffler with valves is a performance-focused upgrade designed for classic Porsche 911 models from 1975 to 1989. Combining modern exhaust technology with the character of air-cooled flat-six engines, this rear silencer enhances sound, responsiveness, and overall driving experience while maintaining a clean, original-style single outlet appearance.
Fits:
Porsche 911 1975 - 1989
Please note: This system does not come with valve control system. You can add it to the basket afterwards.
Featuring a valve-controlled system, this exhaust allows you to switch between a refined, quieter tone for everyday driving and a more aggressive, free-flowing sports sound when desired. This dual-mode functionality gives you the flexibility to enjoy both comfort and performance in one system.
The 1 IN 1 OUT configuration retains a classic factory-style look while improving exhaust efficiency. The freer-flowing internal design helps reduce backpressure, supporting improved engine breathing and throttle response. Performance exhaust systems are widely used to enhance both sound and engine efficiency, delivering a more engaging driving experience.
Manufactured using high-quality materials and precision engineering, this DesignTek muffler is built to withstand the high temperatures and demands of air-cooled engines. Designed as a direct-fit replacement, it integrates with existing exhaust components for straightforward installation and reliable fitment. DesignTek exhaust systems are known for combining performance gains, durability, and easy installation, making them a popular upgrade choice.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
3606001105
91111103100
93011102200
93011104300
The product you are viewing cross references to these numbers
£1,300.00
Now £1,170.00
Arriving soon
Vehicle Group
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
Information
DesignTek Sport Exhaust muffler / silencer rear box, with valves, 1 IN 2 OUT
* tail pipes not included.
The DesignTek 1 IN 2 OUT sports exhaust muffler with valves is a high-performance upgrade designed for classic Porsche 911 models from 1975 to 1989. Combining modern exhaust engineering with classic air-cooled character, this rear silencer enhances both sound and performance while maintaining compatibility with original exhaust layouts.
Fits:
Porsche 911 1975 - 1989
Please note: This system does not come with valve control system. You can add it to the basket afterwards.
Featuring a twin-outlet (2-out) design, this system delivers a more aggressive and sporty appearance compared to standard single-outlet silencers, while also improving exhaust gas flow. The valve-controlled system allows you to switch between a refined, quieter exhaust tone and a louder, more aggressive sports sound, giving you flexibility for both everyday driving and spirited use.
Performance exhaust systems like this are designed to reduce backpressure and improve airflow, helping the engine breathe more efficiently and potentially improving throttle response. A freer-flowing exhaust also produces a deeper, more pronounced flat-six exhaust note, enhancing the overall driving experience.
Constructed from high-quality materials and engineered to withstand the heat and vibration of air-cooled engines, this DesignTek muffler offers durability alongside performance gains. It is designed as a direct-fit replacement, making it suitable for restoration projects, upgrades, or replacing worn original silencers.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
3606001104
The product you are viewing cross references to these numbers
* tail pipes not included.
The DesignTek 1 IN 2 OUT sports exhaust muffler with valves is a high-performance upgrade designed for classic Porsche 911 models from 1975 to 1989. Combining modern exhaust engineering with classic air-cooled character, this rear silencer enhances both sound and performance while maintaining compatibility with original exhaust layouts.
Fits:
Porsche 911 1975 - 1989
Please note: This system does not come with valve control system. You can add it to the basket afterwards.
Featuring a twin-outlet (2-out) design, this system delivers a more aggressive and sporty appearance compared to standard single-outlet silencers, while also improving exhaust gas flow. The valve-controlled system allows you to switch between a refined, quieter exhaust tone and a louder, more aggressive sports sound, giving you flexibility for both everyday driving and spirited use.
Performance exhaust systems like this are designed to reduce backpressure and improve airflow, helping the engine breathe more efficiently and potentially improving throttle response. A freer-flowing exhaust also produces a deeper, more pronounced flat-six exhaust note, enhancing the overall driving experience.
Constructed from high-quality materials and engineered to withstand the heat and vibration of air-cooled engines, this DesignTek muffler offers durability alongside performance gains. It is designed as a direct-fit replacement, making it suitable for restoration projects, upgrades, or replacing worn original silencers.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
3606001104
93011102200
93011102203
93011104300
The product you are viewing cross references to these numbers
£1,250.00
Now £1,125.00
Arriving soon
DISPLAYING 1 to 4 (of 4 products)
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About Sport Silencers / Mufflers
Porsche Sport Silencers & Mufflers - Performance Sound & Exhaust Upgrades
Sport Silencers / Mufflers are designed to enhance the sound, performance, and driving character of your Porsche by improving exhaust gas flow and delivering a more engaging exhaust note. Compared to standard exhaust silencers, sports mufflers reduce restriction, sharpen throttle response, and provide a sportier tone that better reflects Porsche’s performance heritage.
Available from Design911, this category includes both genuine Porsche sport exhaust components and high-quality aftermarket performance mufflers, giving owners the choice between factory-engineered authenticity and performance-focused customisation.
What Do Sport Silencers / Mufflers Do?
Sport silencers optimise exhaust flow while enhancing sound quality.
Core Functions:
- Reduce exhaust backpressure for improved engine breathing.
- Enhance throttle response and power delivery.
- Produce a deeper, sportier exhaust note.
- Improve exhaust efficiency and flow dynamics.
- Enhance the overall driving experience.
A well-designed sports muffler balances performance gains with refined sound control.
Why Do Standard Exhaust Silencers Fail or Fall Short?
Standard exhaust mufflers are designed primarily for noise
reduction, emissions compliance, and longevity. Over time, common issues
include:
- Internal corrosion from condensation and heat cycles.
- Restrictive baffling limiting exhaust flow.
- Dull or muted exhaust sound.
- Internal baffle breakdown causing rattles.
- Reduced efficiency when paired with performance upgrades.
As these components age, both performance and sound quality can deteriorate.
Why Upgrade to Sport Silencers / Mufflers?
Sport silencers are engineered to improve both performance and auditory feedback.
Upgrade Benefits:
- Improved exhaust flow and reduced restriction.
- Enhanced exhaust sound without excessive drone.
- Increased driving engagement and responsiveness.
- Available in OEM Porsche or performance aftermarket options.
- Ideal for road, touring, and spirited driving.
Upgrading delivers a more exciting exhaust character while supporting engine efficiency.
Highlights
- Porsche sport silencer and muffler upgrades
- OEM Porsche and premium aftermarket options
- Improved exhaust sound, flow, and performance
- Designed for performance-focused driving
- High-quality materials for durability and reliability
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All Silencers / Mufflers
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Catalyst / Bypass
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Manifold / Headers
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Exhaust Tail Pipes
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Heat Exchangers
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Exhaust Pre-Silencer
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Exhaust Cross over pipes
-
Exhaust Package
-
Exhaust Gaskets
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Exhaust Nuts / Bolts / Studs
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Brackets / Clamps / Straps
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Exhaust Fitting Kits
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Fabspeed Exhaust
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Lambda Sensors / Probes
-
Lambda Sensor Extensions
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