The MMX Performance F8X S55 Power Control Module is a clean-sheet alternative to traditional ECU tuning for the S55-powered M2 Competition, M3, and M4. After more than 12 months of in-house development, the PCM is far more than a piggyback box, it functions closer to a secondary ECU, with a standalone PCB running MMX’s own calibration and communicating in parallel with the factory ECU to optimize charge air pressure, ignition, and fueling in real time.

The result is a substantial increase in power and torque across the entire powerband, but delivered the way MMX prefers: smoothly, safely, and reliably, without compromising drivability or efficiency. The PCM keeps the OEM ECU intact and untouched, which is what enables the headline benefit: it’s completely removable, leaves no trace, and is undetectable when removed. For owners who want serious gains without committing to a flashed ECU, this is the cleanest path on the platform.

Each module is housed in a finned billet aluminum case, anodized in MMX gloss black, and mounted on a carbon fiber bracket. The wiring loom is vehicle-specific, every SKU corresponds to a particular S55 variant, with calibration tuned for that car’s stock output. Installation is plug-and-play into the engine bay sensor harness; no ECU removal, no permanent modifications, no special tools required.

Painstakingly engineered and hand-assembled in the UK to OEM-level quality.

Product Details

• Standalone PCB with MMX in-house calibration
• Fully removable and undetectable once removed
• Billet aluminum case, finned for cooling, MMX gloss black anodized
• Carbon fiber mounting bracket included
• Vehicle-specific wiring loom: select your variant from the dropdown

What’s Included

• PCM unit (billet aluminum finned case)
• Vehicle-specific wiring loom
• Carbon fiber mounting bracket and hardware

Variant Output

• MMR50-1603: F87 M2 Competition: stock 405 HP / 550 Nm to 494 HP / 625 Nm (+89 HP / +75 Nm)
• MMR50-1604: F87 M2 Competition Sport: stock 444 HP / 550 Nm to 494 HP / 625 Nm (+50 HP / +75 Nm)
• MMR50-1605: F80 M3 / F82/F83 M4 Competition: stock 450 HP / 550 Nm to 520 HP / 660 Nm (+70 HP / +110 Nm)
• MMR50-1606: F80 M3 / F82/F83 M4 (base): stock 431 HP / 550 Nm to 510 HP / 650 Nm (+79 HP / +100 Nm)
• MMR50-1607: F80 M3 / F82/F83 M4 Competition Sport: stock 460 HP / 600 Nm to 520 HP / 670 Nm (+60 HP / +70 Nm)

Notes

• F87 M2 (N55 engine) is NOT compatible with this S55 module.
• Includes a 1-year manufacturer warranty against defects in materials and workmanship
• Designed and tested in the United Kingdom
• View emissions compliance notice
• Not for sale or use in California