Audi
RS6 Avant C8 · 2020 – present
Make your estate sound like the wagon it should be. Full twin-turbo V8 voice, on tap, without touching the exhaust.
- Suits RS6 Avant and RS7 Sportback C8
- Holds both valve banks open simultaneously
- Hidden install — module tucks behind the rear trim
- Original valve operation restored at the press of a button
Free UK shipping
2-year warranty
Fully reversible
The honest pitch
What this actually does to your RS6 Avant
The C8 RS6 has one of the best-sounding V8s of the decade and Audi keep it on a very tight leash. Even RS2 mode lets the valves cycle shut at part throttle.
Open Valve hands the decision back to you. It intercepts the actuator command so the flaps stay where you want them — wide open — for as long as you want them there.
Drop the kids at school in silent mode. Press one button on the way back through the village. The Avant remembers who it is.
Fitment
Audi RS6 Avant C8
Years
2020 – present
Install time
~10 minutes
Tools needed
None
Long read
The Audi RS6 Avant valve story
The C8 RS6 Avant is one of the great-sounding modern V8s and Audi knew it would not get past European drive-by noise tests if they let it sing in cruise. The valve map on every C8 we've worked on — RS6 Avant, RS6 Performance, RS7 Sportback — opens the rear flaps for hard launches and shuts them again everywhere else. Even RS2 individual mode doesn't lock them open; it just biases the map.
Open Valve pins both rear actuators open. The 4.0 TFSI twin-turbo V8 then runs the way it does at full chat, all the time. The cylinder-on-demand stuff stays active — the module doesn't touch the V8/V4 deactivation logic, which lives entirely in the engine itself. So you still get the cylinder-deactivation efficiency on the motorway. You just hear the full V8 the rest of the time.
We've measured these cars at +5 dB at the bumper at 2,500 RPM cruise with the flaps held open versus the same RPM with flaps closed in Comfort. That's a meaningful step — not aftermarket-back-box loud, but the difference between 'a saloon' and 'an angry V8 saloon'. Decel pops on lift come back, especially in Dynamic above 4,000.
Fitment on the RS6/RS7 C8 takes about twenty minutes. Two actuator motors, one per rear silencer. You access them by lowering the rear of the underbody panel — six T25 screws. The connectors are the same Audi 2-pin grey as the RS3.
Important: this is the rear flap only. The mid-pipe X-flap (where fitted on Performance cars) is not affected, but that flap is normally held open at all RPM anyway so it doesn't change the audible result. If you have aftermarket Akrapovic or Capristo back-boxes that retain OEM actuators, the kit still works.
Install — step by step
- 01
Raise the car on a proper four-poster or solid axle stands. The underbody panels are heavy and you need both hands.
- 02
Remove the six T25 torx screws holding the rear underbody panel. Lower it carefully — it weighs about 5 kg.
- 03
Unclip both grey 2-pin valve actuator connectors from the rear silencer actuator motors.
- 04
Plug each module inline. Tuck the module body up against the chassis rail with the supplied heat-rated velcro.
- 05
Refit the underbody panel. Tighten all six screws to 8 Nm.
- 06
Pair the fob, test on idle. Both rear flaps should click open simultaneously when you press the top button.
In the box
- Two valve override modules (one per actuator)
- Two-button RF key fob (CR2032 pre-installed, spare in the box)
- OEM-pattern connectors — no cutting, no splicing, no scotch-locks
- Printed install card with model-specific photos and a workshop QR link
Fitment notes
- ·C8 RS6 Avant, RS6 Performance, RS7 Sportback, RS7 Performance — all supported.
- ·Pre-facelift and facelift cars share the same actuator pinout.
- ·Owners with aftermarket valved back-boxes (Akrapovic, Capristo) using OEM actuators: kit works unchanged.
Audi RS6 Avant — FAQ
Does it work on the RS6 Performance and RS7 Performance?+
Yes. The 2023 onwards Performance variant uses the same actuator hardware. Same module, same install.
What about the cylinder-on-demand fuel saving — does this disable it?+
No. The module sits at the exhaust valve actuator only. The V8-to-V4 cylinder deactivation logic lives in the engine ECU and is unrelated. You keep the motorway fuel saving exactly as Audi designed it.
Will it throw a warning light on the dash?+
No. The module sits in the signal path between the ECU and the actuator motor. The ECU sees a normal actuator response back, so there's nothing to flag. We've shipped thousands of these and not had a single check-engine call linked to the module itself.
Is it reversible?+
Yes, fully. Unplug the module, plug the OEM connectors back into each other, refit the trim — about three minutes' work. There's no permanent change to the car, no part cut, nothing in the ECU. Dealer service visits, MOT, sale to a new owner — pull it out and it's like it was never fitted.
Does it work with an aftermarket exhaust?+
If the aftermarket back-box retains the OEM-pattern valve actuators (most do — Akrapovic, Milltek, IPE, Capristo all run the factory motors), yes. If the system is a straight-through with no valves, there's nothing for the module to override.
Will it pass an MOT?+
We sell these for off-road use only. UK MOT noise testing is subjective and a stock back-box held open generally passes; testers in Germany and the Netherlands are stricter. If you're in a noise-checked region, flip the fob to OFF before the test.
Does the module interfere with adaptive air suspension or quattro logic?+
No. The module touches two wires only — the actuator signal to each rear valve motor. Suspension, drive, gearbox and torque-vectoring systems read entirely different sensors and stay unaffected.
Disclaimer
Open Valve modules are intended for off-road and motorsport use only. Please confirm your car has factory valve-actuated exhaust before ordering — if you're not sure, message us first. Professional installation recommended. Use at your own risk.
