McLaren
720S — · 2017 – 2023
Set the 4.0 twin-turbo V8 free at every RPM, in every handling mode.
- Specifically validated against 720S valve hardware
- No effect on Variable Drift Control or Active Dynamics
- Plug-and-play to OEM actuator harness
- Removable in minutes for service visits
Free UK shipping
2-year warranty
Fully reversible
The honest pitch
What this actually does to your 720S
Woking gave the 720S a deeply engineered exhaust system and then a fairly restrained acoustic map. Track mode lets the engine sing — most of the time, anyway.
This adaptor leaves every electronic system untouched and simply keeps the exhaust valves open whenever you press the fob. The 720 sounds the way it does at Goodwood, on every B-road.
Fitment
McLaren 720S —
Years
2017 – 2023
Install time
~10 minutes
Tools needed
None
Long read
The McLaren 720S valve story
Woking shipped the 720S with one of the most over-engineered exhaust systems in the supercar class and one of the most restrained valve maps. Track mode opens the rear flaps in narrow windows. Sport opens them less often. Normal effectively keeps them shut at part throttle. The result, walking past a 720S in Normal at 30mph, is something closer to a Bentley than a McLaren.
Open Valve overrides the close command at the actuator. The 4.0 twin-turbo V8 then runs at its loudest profile across every handling mode. The induction whoosh, the off-cam burble at low revs, the metallic crack on downshift — all of it comes through at every throttle position.
Install on the 720S is the most delicate in our catalogue because the rear deck and engine cover panels need to come off properly. We strongly recommend a McLaren-experienced workshop fit the kit. Expect a competent tech to take 90 minutes the first time, mainly because of the trim disassembly.
Variable Drift Control, Active Dynamics Panel, all the Proactive Chassis Control logic — none of it is touched. The module is signal-level on two wires.
Install — step by step
- 01
McLaren-experienced workshop fitment recommended.
- 02
Remove the rear deck panel and engine cover trim per McLaren WSM procedure.
- 03
Locate both rear valve actuator motors on the silencer body.
- 04
Disconnect each 2-pin connector. Plug each module inline.
- 05
Mount module bodies to the rear chassis structure using supplied heat-rated brackets.
- 06
Refit all trim per WSM torque specs.
- 07
Pair fob, test on idle.
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
- ·720S Coupé and Spider (2017–2023). 765LT supported with a different firmware variant — contact us first.
- ·Workshop fitment recommended due to rear trim complexity.
- ·Compatible with OEM exhaust only; aftermarket Inconel systems without OEM actuators are not.
McLaren 720S — FAQ
Does it work on the 720S Spider as well as the Coupé?+
Yes — same actuator hardware. Same kit.
What about the 750S?+
The 750S uses very similar hardware but a slightly different signal calibration. A separate module is available — pick it at checkout.
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 dealer diagnostics see the module?+
No. The module is electrically transparent. McLaren MDS does not detect it.
Is there any effect on Variable Drift Control or PCC?+
No. VDC, PCC, Active Dynamics, ESC — all read separate sensors. 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.
