String Theory Garage will be closed to the public from Wednesday, 29th July to Thursday, 6th August for our annual shutdown.
If you need to get in touch, please leave us a voicemail or send an email. Our team will happily get back to you when we return on Friday, 7th August.
Shopping online? Don't worry! Our online store will remain active! We hope to ship orders placed for in-stock items as normal during the shutdown. Anything else will be dealt with upon our return.
Thank you for your understanding, String Theory Garage Team
Unlock more power and torque with just one click! Choose your vehicle to get started.
With multiple channels such as charge air pressure, ignition and fuelling controlled by the PCM computer, the result is increased power and torque across the whole powerband of the engine.
BMW F87 M2 Competition (S55)
Stock figures: 405 HP & 550 Nm
PCM figures: 494 HP & 625 Nm
+89 HP +75 Nm
BMW F87 M2 Competition Sport (S55)
Stock figures: 444 HP & 550 Nm
PCM figures: 494 HP & 625 Nm
+50 HP +75 Nm
The MMX PCM is an advanced engine tuning solution, using proprietary calibration on a standalone PCB that communicates in parallel with the factory ECU. This setup allows real-time optimisation of key sensor signals, enhancing engine performance without overriding OEM safety systems.
Developed over 12 months and tested across tens of thousands of miles—on dyno, road, and track—the MMX PCM delivers the ideal balance of power, drivability, and reliability. It’s far more than a standard tuning box—functioning more like a secondary ECU.
Each kit includes a custom-fit wiring loom for your specific vehicle. The PCM module is enclosed in a finned billet aluminium case for efficient cooling and comes with a carbon fibre mounting bracket for secure, clean installation.
