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- Porsche 991.2 Speedster 4.0L (510Bhp) 2019
- Porsche 991.2 GT3 4.0L (500 Bhp) / GT3 RS 4.0L (520 Bhp) 2017-19
Fits:
Porsche 911 GT3 RS (991.2) with OPF/GPF 2019 - 2020
Porsche 911 Speedster with OPF/GPF 2019 - 2020
Evolution Header Set (Titanium) must be mounted together with:
• Slip-On Line (Titanium) system S-PO/TI/15
or
• Slip-On Race Line (Titanium) system S-PO/TI/8.
An additional original Porsche stock bracket (Porsche p/n: 99111147391) is required for mounting the Akrapovič exhaust system. Please read the instructions carefully before the start of the installation.
Evolution Header Set converts the slip-on system into a full system designed to give noticeably increased power at higher revs. Handcrafted titanium headers incorporate 100 cpsi sports catalytic convertors and side mufflers—all designed to increase power and torque—the Evolution Header Set utilizes integrated catalytic convertors and the functionality of the exhaust valves to deliver an out-and-out attack on the senses. With the valves in the open position, it delivers a sportier and hard-hitting sound, but also has the option of a lower sound level when the valves are closed, perfect for use in more everyday locations. Offering an increased weight savings in the area behind the engine and the rear axle, the reduction will enhance the handling and improve performance.
When installing Akrapovič aftermarket optional link pipes with sports catalytic converters or without catalytic converters, which are developed for use on closed tracks only, remapping the ECU is mandatory. When installing Akrapovič aftermarket exhaust system that was developed for use on closed tracks, we recommend remapping the ECU in order to prevent potential »check engine light« warning signals.
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Related, superseded, cross reference or alternative numbers for comparison.
E-PO
The product you are viewing cross references to these numbers
- Porsche 991.1 GT3 3.8L (475Bhp) 2014-16
- Porsche 991.1 GT3 RS 4.0L (500Bhp) 2015-16
- Porsche 991.2 Speedster 4.0L (510Bhp) 2019
- Porsche 991.2 GT3 4.0L (500 Bhp) / GT3 RS 4.0L (520 Bhp) 2017-19
- Porsche 991.2 GT2 RS 3.8L PDK (700 bhp) 2018-19
Bypass pipes for side mufflers.

Fits
Porsche 911 GT3 and GT3 RS (991.1 and 991.2 2014-2019)
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
Material: Stainless Steel 304
Replacement for Genuine muffler 991.111.048.81
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
3606609140
The product you are viewing cross references to these numbers
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