ASR RX1 exhaust flaps, Audi S4, S5 (B9) / S8

Adjust the exhaust sound to your liking with the ASR controller. This control system connects to the factory-installed exhaust flap valves, which are normally controlled by the manufacturer’s logic based on different driving modes and situations. In its original form, the flap operation is often quite conservative, keeping the noise level modest in most situations. Depending on the car, the flaps may not fully open in any situation with the original settings.

The controller connects to the original flap motor wiring harness with ready-made connectors, and it’s available at your discretion – you can also bypass the system, allowing the flaps to work as they did originally.

• Freely choose how the exhaust flaps operate by clicking on the remote control
• Plug-n-play installation is cleanly removable and does not require modifications like altering wiring harnesses
• You can bypass the function, and the flaps will continue to operate as standard
• Does not cause disturbances or issues with the car’s CAN-bus or control units

Device operating modes:

• RACE = In this mode, the exhaust flaps are fully opened by pressing button 1.
• OEM = In this mode, the system is controlled by the car’s own logic, and the ASR is disabled.
• SILENT = In silent mode, the exhaust flaps are forced closed, for example, when you want to avoid waking up the neighbors early in the morning.

The device is programmable according to your preference for which mode it starts in when the vehicle is started.

ASR exhaust flap controller installation

The installation is easy with the ready-made wiring harness. In most models, the equipment is most easily placed in the trunk, where you can typically use the original grommets for the wiring harness.
All the products we sell can also be installed at our Vantaa service point. Contact us for more information!

Please note your local law and regulations

The exhaust flaps are originally controlled to ensure the car meets the defined regulations and noise limits for road use.
Modifying the control of flap valves is NOT permitted on public roads – the device is only for use on track days, in racing, or other closed environments for your enjoyment.

Compatible car models:
S4 B9
S5 B9 F5
S8 D4
S8 D5
A8 60 TFSI D5