Factory exhaust systems are increasingly designed around multiple driving modes, active exhaust valves, and increasingly complex electronic controls.

That gives manufacturers the ability to balance performance, refinement, emissions, and noise requirements.

But for enthusiasts, it can also mean that the exhaust does not always sound the way you want it to.

SST Spezialsteuergeräte offers a solution with application-specific exhaust flap and valve controllers designed to give the driver direct control over the factory exhaust flap system.

Made in Germany and developed for specific vehicle applications, SST controllers allow you to choose how the exhaust valves behave instead of relying exclusively on the factory programming.

Direct Control Over Your Exhaust Flaps

The primary purpose of an SST controller is straightforward: give the driver control over the vehicle's active exhaust valves.

Depending on the application, the controller can allow the exhaust flaps to remain open, remain closed, operate according to the factory strategy, or sit at a partially open position for a customized sound profile.

The system is designed as a plug-and-play solution that works with the vehicle's existing exhaust flap system.

This makes SST particularly useful for vehicles where the factory exhaust programming does not provide enough control over the sound.

Sport, Comfort, Factory, and Freestyle Modes

One of the biggest advantages of SST controllers is the ability to select different operating modes.

Sport Mode

Sport mode keeps the exhaust flap or flaps permanently open.

This allows more of the exhaust note to reach the outside of the vehicle, producing a louder and more aggressive sound.

Comfort Mode

Comfort mode keeps the flaps closed for a quieter and more restrained exhaust note.

This can be useful when driving through residential areas, commuting, or simply when a quieter driving experience is preferred.

Factory Mode

Factory or Serial mode returns control to the vehicle's original exhaust strategy.

The factory system can therefore operate normally when required, including for service or situations where the OEM behavior is preferred.

Freestyle Mode

Freestyle mode provides an intermediate setting.

Depending on the controller and vehicle application, the exhaust flap can be held partially open, such as at approximately 50%, allowing the driver to create a sound level between the fully open and fully closed settings.

Application-Specific Engineering

SST does not rely on a universal controller for every vehicle.

The XPH catalog includes vehicle-specific SST controllers developed for individual platforms and exhaust configurations.

BMW applications include models such as the 1 Series, 2 Series, 3 Series, 5 Series, M3, M4, X3 M, X4 M, X7, and newer M5 applications.

For example, SST offers controllers for the BMW G20/G21/G28 3 Series, including the 330i, 330e, and M340i, while separate systems are available for M3 and other performance applications.

BMW M Cars and Performance Models

SST controllers are particularly relevant to BMW M vehicles equipped with active exhaust systems.

Applications available through XPH include controllers for platforms such as:

• BMW F80 M3
• BMW G80 M3
• BMW G87 M2
• BMW F82/F83 M4
• BMW G82/G83 M4
• BMW X3 M F97
• BMW X4 M F98
• BMW M5 applications
• Other BMW models with electronically controlled exhaust flaps

For newer BMW applications, SST provides vehicle-specific controllers rather than requiring modifications to the factory exhaust hardware.

Audi and Volkswagen Performance Applications

SST also offers exhaust flap controllers for Audi performance vehicles.

The XPH catalog includes applications for models such as:

• Audi S4
• Audi S5
• Audi S6
• Audi S7
• Audi Q8
• Other Audi performance applications

Depending on the system, the controller can provide Sport, Comfort, Factory, and Freestyle modes, along with memory functionality and additional flap monitoring on DELUXE versions.

This makes SST a useful option for Audi owners who want greater control over an electronically controlled exhaust without replacing the entire exhaust system.

Mercedes-AMG Applications

SST also covers a wide range of Mercedes-Benz and AMG vehicles.

The systems are designed to work with the factory exhaust flap arrangement and can provide direct control over the exhaust valves.

For example, SST offers a controller for the Mercedes-AMG S63 using the W217 and W222 platforms from 2013 through 2017. The system is compatible with both factory and sports exhaust flap systems.

Other Mercedes applications extend across AMG performance models and SUVs.

Porsche Applications

Porsche owners can also use SST controllers to alter the behavior of active exhaust systems.

The range includes controllers for multiple Porsche platforms, including the 911, Cayenne, Boxster, and Panamera.

Newer applications include the Porsche 911 Type 992.2, where SST provides a controller capable of operating two exhaust flaps and includes a discreet, waterproof installation configuration.

For older Porsche applications, SST also offers systems for models such as the 981 Boxster and 970 Panamera.

Lamborghini and Exotic Applications

SST's catalog extends beyond German vehicles into high-performance exotic applications.

Lamborghini controllers are available for vehicles including:

• Lamborghini Gallardo
• Lamborghini Huracán
• Lamborghini Aventador
• Lamborghini Urus
• Lamborghini Centenario
• Lamborghini Countach
• Lamborghini Sián
• Lamborghini Revuelto
• Other select Lamborghini applications

The Revuelto system, for example, uses an IP66-rated control unit and provides Sport, Comfort, Factory, and adjustable Freestyle operation.

Older Lamborghini applications are also supported, including the Gallardo, where SST provides a compact, waterproof controller designed for discreet installation.

Memory and Startup Functions

SST controllers can also provide more flexibility than simply selecting a mode each time you drive.

Depending on the application, the controller can be configured to remember the last selected operating mode.

Alternatively, a specific mode can be configured to activate automatically whenever the vehicle is started.

This allows drivers to establish their preferred exhaust behavior without repeatedly changing the setting after every ignition cycle.

Exhaust Flap Calibration

Some SST systems also include a function for retraining the mechanical stops of the exhaust flaps.

This can be useful when an exhaust flap has been replaced or when a flap is installed into another compatible exhaust system.

The controller can retrain the flap's mechanical positions so that the system can correctly recognize its operating range.

DELUXE Flap Diagnostics

Selected SST controllers are available with DELUXE functionality.

In addition to controlling the exhaust valves, the system can continuously monitor the flap operation and detect issues such as a flap becoming jammed, moving sluggishly, or failing to reach its expected end position.

When a malfunction is detected, the system can report the issue to the vehicle.

This adds another layer of functionality beyond simply changing exhaust sound.

Designed for Factory and Aftermarket Exhaust Systems

SST controllers can be used with compatible factory exhaust systems and can also be particularly effective when paired with a performance exhaust.

Controlling an existing active exhaust valve gives the driver additional flexibility without necessarily requiring a complete exhaust replacement.

For vehicles already equipped with a valved sports exhaust, SST can provide another way to manage the system's operating behavior.

Compact, Discreet Installation

SST controllers are designed to be installed discreetly.

Depending on the vehicle, the control unit can be positioned in locations such as the trunk or behind the bumper. Some applications use waterproof housings suitable for installation in exposed areas, while other systems are installed in the engine compartment with additional protection for the wiring.

The controllers are also designed not to consume quiescent current when switched off, helping prevent unnecessary load on the vehicle's electrical system.

Why Choose SST Spezialsteuergeräte?

SST focuses on one specific part of the driving experience and develops its products around that function.

The result is a range of application-specific exhaust valve controllers offering:

• Plug-and-play installation
• Vehicle-specific programming
• Multiple operating modes
• Adjustable exhaust sound
• Factory exhaust compatibility
• Memory functionality
• Exhaust flap calibration
• Optional flap diagnostics
• Compact and discreet control units
• German manufacturing

For enthusiasts who want more control over their vehicle's exhaust behavior, SST provides a way to change the experience without necessarily changing the entire exhaust system.

Explore SST at XPH

At XPH, we offer SST Spezialsteuergeräte exhaust flap and valve controllers for a wide range of BMW, Audi, Mercedes-AMG, Porsche, Lamborghini, and other performance applications.

Whether you want a more aggressive exhaust note from your BMW M car, greater control over an Audi or AMG's active exhaust, or adjustable valve behavior on an exotic performance vehicle, SST provides application-specific solutions designed to put control back in the driver's hands.

Explore SST Spezialsteuergeräte at XPH: https://x-ph.com/sst-spezialsteuergerate/