Mobile BMW & Supra tuning · E-series · F-series · G-series
MHD is one of the most popular mobile ECU tuning platforms for BMW and Toyota Supra. Flash tuning software, record datalogs, monitor live engine data, read & clear faults, and manage advanced MHD+ features directly from your phone or tablet. At SamuelTuned, MHD is used for custom BMW remote tuning anywhere in the world.
What it is
MHD is a mobile ECU flashing and tuning platform built around BMW and Toyota Supra. Supported vehicles flash through the OBD port using a smartphone, tablet and the right connection hardware.
Unlike a piggyback box, MHD writes tuning software to the factory ECU/DME — proper control over the calibration while keeping the factory ECU management system. The car flashes, logs and behaves like the manufacturer intended, just running your file.
The platform
MHD is the app and flashing platform — it connects to the ECU and handles writing, logging and monitoring.
The tune
The tune is the calibration file loaded into the car — what controls boost, fuelling, timing and torque.
MHD makes the workflow possible. The performance, safety and drivability of the car comes from the quality of the calibration loaded through it.
What it lets you do
Why use MHD?
MHD is one of the most convenient platforms for BMW tuning because it is built mobile-first. Connect, flash, log and adjust without a complicated laptop setup. Once your licence and hardware are in place, the workflow runs from your phone — files in, datalogs out, revisions back.
Supported vehicles
Compatibility depends on exact model, engine, ECU type, production date and software version. Some cars need an ECU unlock first — see below.
The N54 is the engine that put MHD on the map and remains a major platform — single turbo conversions, upgraded twins, port injection and full ethanol setups all live here.
Common models
A wide N55 platform across BMW performance models. Stage 1, Stage 2, hybrid turbo and ethanol blends all flash through MHD.
Common models
Modern B58 cars respond extremely well to MHD calibration — especially with the right hardware and fuel.
Common models
S55 cars vary heavily based on hardware, cooling, turbo condition and fuel — exactly where custom MHD calibration earns its keep.
Common models
Modern BMW M cars on the S58 platform — once unlocked, MHD covers flashing, datalogging and full custom map revisions.
Common models
Note · Most newer S58 vehicles require ECU unlocking before MHD can flash. Once unlocked, the full workflow is available.
Big-power BMW M applications. Accurate datalogging and controlled revisions are critical at this torque level.
Common models
The 2020+ Supra is BMW B58 underneath — Stage 1 through big-turbo custom remote tuning, end-to-end through MHD.
Common models
Hardware
Coming soon to this site — the right adapter, cable and licence for your car, in one place.
The easiest connection method for modern BMW and Supra. Wireless flashing, datalogging, diagnostics and monitoring — works across E-series, F-series, G-series and Supra A90/A91, on Android and iOS.
A wired ENET cable for supported F-series, G-series and Supra applications. Reliable for flashing — kept as a backup connection by some customers.
For older BMW E-series cars (notably N54 and certain N55 platforms). Choosing the right connection method matters — the wrong cable will simply refuse to connect.
Inside the platform
Flash the factory ECU through OBD on supported BMW and Supra vehicles. Install, update and revise software without removing the ECU.
Records boost, throttle closure, timing, knock, lambda, fuel pressure, torque limits and more. Every custom MHD revision is reviewed against real ECU data.
Real-time view of boost, fuel pressure, intake temperatures, ignition timing, ethanol content and lambda. Useful long after the tune is finalised.
Run different map slots — pump fuel, ethanol, race fuel, low-boost, high-boost, valet, track, drag — without re-flashing.
Compatible cars adjust calibration based on real-time ethanol content. No more flashing a different file each time the blend changes.
E40 N54, E85 S55, E30/E40/E50 B58, S58 ethanol — all matched to your fuel system, turbo and actual ethanol content.
Faster boost response on supported setups — most relevant on hybrid/big turbo builds and drag/roll-race cars. Configured around your actual hardware.
Adjustable overrun behaviour and exhaust valve control. Tuned sensibly — burble that bakes catalysts is not on the menu.
MHD+ supports torque/power adjustment by gear — useful for traction management on tuned BMWs where the lower gears get traction-limited.
OTS vs custom
OTS-style MHD maps work fine on a near-stock car. They are not built around your engine, your fuel, your turbo or your datalogs — and that limits how far they can take you.
Off-the-shelf
Designed to work across a wide range of cars. Limitations to be aware of:
Built for you
A custom MHD tune is the right route once your car has supporting hardware, ethanol or specific performance goals. The calibration is built around your actual setup and revised against real datalogs until the car behaves correctly.
Especially useful for
Tune stages
Stage 1
Common on 135i, 335i, M135i, M235i, M140i, M240i, 340i, 440i, F80 M3, F82 M4, G80 M3, G82 M4 and Supra 3.0. Improved power and drivability without major hardware.
Stage 2
Downpipe, intake, charge pipe, intercooler, exhaust, upgraded fuel pump, plugs and cooling. Strong fit on N54, N55, B58, S55, S58 and Supra.
Hybrid / Big turbo
A generic file is rarely the right answer with a larger turbo — airflow, boost control and torque behaviour change completely. Custom calibration around your actual hardware and datalogs.
Remote tuning
Step 01
You'll need the correct MHD hardware to connect to the car — typically the MHD Universal WiFi Adapter. Available directly from this site.
Step 02
Install MHD, register your vehicle and activate the licence covering your engine family.
Step 03
Newer BMW G-series and modern Bosch MG1/MD1 ECUs need to be unlocked first. If yours is locked, that step happens before any flashing.
Step 04
Samuel issues your first calibration file. You flash it through MHD from your phone.
Step 05
You drive the car under the requested conditions and record the datalogs Samuel asks for.
Step 06
Samuel reviews the logs, refines the calibration and sends a revised file. You re-flash and run another log set.
Step 07
Once the data shows the car behaving exactly as it should, the calibration is finalised and you keep driving.
ECU unlock
Newer BMW G-series cars, S58 models and modern Bosch MG1/MD1 ECUs typically need to be unlocked before MHD can flash them. If yours is locked, MHD won't write any tuning software until the unlock is completed.
ECU unlock guideUnlock typically required for
Before we start
Getting these right makes the tune faster, cleaner and safer.
FAQ
Anything else, message Samuel directly — every MHD build is different.
A mobile ECU flashing and tuning platform for supported BMW and Toyota Supra vehicles. ECU flashing, logging and monitoring through a phone or tablet using compatible connection hardware.
Yes — MHD is one of the strongest platforms for remote BMW tuning. Flash files, record datalogs and receive revisions without visiting a workshop.
Different connection methods are supported, but the MHD Universal WiFi Adapter is the easiest option for most customers — it makes flashing, logging and revisions much simpler.
Yes — MHD hardware will be available to purchase directly from this site.
Yes — MHD supports both Android and iOS depending on the vehicle and connection hardware.
Yes — all three are MHD+ features supported on compatible vehicles and setups.
No. If your ECU requires unlocking, that has to happen before MHD can flash any tuning software.
For a near-stock car, an OTS map can be enough. For modified cars, ethanol setups, upgraded turbos, track cars or drag cars, a custom MHD tune is the right route.
Ready to start
Whether you already have MHD or are starting from scratch, the process can be handled remotely from anywhere in the world.