M-Engineering ProTune for McLaren M840T (720S, 765LT, Senna, GT)

The M-Engineering ProTune is a custom calibration for McLaren's 4.0-liter M840T twin-turbo V8, the engine in the 720S, 765LT, Senna and GT. It is for owners who already run the M-Tuner Calibration Suite for M840T and want every ounce of safe power from their car, or who have a parts configuration that M-Engineering's map notes do not cover.

Instead of an off-the-shelf map, M-Engineering customizes the calibration for your car, either remotely or at its South Florida dyno facility. A ProTune purchase covers one octane, and additional octane maps are available at extra cost. Choose Yes in the option above if your McLaren has upgraded turbos or injectors: M-Engineering charges more for those cars because of the added complexity of tuning upgraded fuel or turbo systems.

Installation depends on M-Tuner. M-Tuner on a McLaren needs a one-time bench unlock, with the ECU removed and mailed to M-Engineering HQ. Once that is done, calibrations are flashed over OBD-II with M-Tuner, so the ProTune itself does not need another ECU removal. Using a dyno is highly recommended and in most cases required, and dyno rental is not included.

Key specs

Features

• Custom calibration built for your car and parts
• Remote tuning or a session at M-Engineering's South Florida dyno facility
• Suited to parts configurations not covered by the M-Tuner map notes

What is included

• A custom M-Engineering calibration for one octane
• A tuning time block of up to seven hours
• Delivery through your existing M-Tuner suite

Requirements before your ProTune

• The M-Tuner Calibration Suite for M840T, which needs the one-time ECU bench unlock.
• A dyno is highly recommended and in most cases required; dyno rental is not included.
• M-Engineering recommends PWM-controlled fuel pump upgrades and will not tune pump setups that use a Hobbs switch. The 750S, 765LT and Senna run twin brushless pumps from the factory, and these can be fitted to the 720S.
• A signed liability waiver is required before tuning.

Frequently asked questions

Is this a bench flash or an OBD flash?
OBD. The ProTune is loaded through M-Tuner over the OBD-II port. The only bench step is M-Tuner's one-time McLaren ECU unlock, where the ECU is removed and mailed to M-Engineering HQ; if your car already runs M-Tuner, that is done.

How much power will I gain?
M-Engineering does not publish a figure for the ProTune. It is a custom calibration, so the result depends on your fuel, hardware and the car itself.

How is a ProTune scheduled?
It must be booked more than 24 hours in advance and approved by M-Engineering. Sessions run during M-Engineering's business hours, 9 AM to 6 PM ET, Monday to Friday, and a session that runs past those hours needs another day, which is a separate ProTune purchase.

Which option should I choose?
Choose No for a car on stock turbos and injectors. Choose Yes if the car has upgraded turbos and/or injectors.

Fitment notes

For M840T-engined McLarens running the M-Engineering M-Tuner Calibration Suite. US model years are listed below.