Speed Logic · Westminster, CA

MHD Flash Tune for BMWs and Toyota Supra

MHD Flasher app tuning a BMW ECU over the OBD port

What Is MHD Flasher?

MHD Flasher is the first Android and iOS handheld application to bring ECU tuning and monitoring to the BMW N54, N55, S55, B58, S58, S63, and N13 engines. It reveals the significant power BMW leaves on the table from the factory, while retaining the sophistication of the original engine management software.

MHD is a full custom tuning platform for the factory engine computer (DME), available on Windows, macOS, iOS, and Android. Flash a new tune through your car's OBD port from your own driveway — the whole process takes just seconds.

As an authorized MHD dealer, Speed Logic installs your license and map for you in-house — every tune is done by appointment, on the car, with payment collected at the shop. If you're wondering why to tune with MHD: from the factory, BMWs are engineered conservatively and always leave power on the table. A simple flash tune can add meaningful horsepower (HP) and torque (TQ) over stock — no other hardware required.

MHD+ CustomROM Features

Map Switching on the fly using your steering wheel cruise control buttons — flash once and access 4 switchable maps from a single slot to the next.
Flex Fuel Tuning — a Flex Fuel sensor reports ethanol % to the DME, which manages the tune from pump gas (0% ethanol) up to E100 without re-flashing.
AntiLag — build boost while stationary or rolling using the cruise control button and accelerator pedal, for instant boost when roll racing or launching.
New Map Editor — an advanced tuning editor with close to 5,000 tuning tables available.
Datalogging of 80+ advanced RAM channels and hundreds more, at the highest throughput of any tool on the market.
Ethanol In-Dash Indicator — displays Flex Fuel sensor readings on the RPM gauge (e.g. 2,000 rpm = 20% ethanol, 5,500 rpm = 55% ethanol).
Switchable Burble Per Map Slot — fully configure burble on your main map, then adjust aggressiveness and duration independently on every other slot.
On-The-Fly Exhaust Flap Control — set your exhaust flap to always open, always closed (opens under high load), or OEM behavior from the MHD+ Live menu.
Overrun Brap Noise — the signature M-car "brap" on throttle lift-off.
KnockCEL — on custom tunes, the CEL blinks if timing correction reaches a tuner-set threshold.
Custom TCU Limiter Removal (Gen 2 only, currently) — removes the TCU limiter while retaining all safeties and OEM launch control.
No Lift Shift (Gen 2 only, currently) — shift 6MT cars without releasing the throttle for the quickest shifts.

Need an ECU Unlock First?

Some late-model ECUs get locked out of tuning after a dealer software update, a warranty/recall visit, or an over-the-air update — this can affect certain Toyota Supra A90/A91, BMW S55, and BMW B58 ECUs. If your ECU is affected, it needs to be bench-unlocked before an MHD tune can be installed. Ask us about ECU Unlock eligibility and the process when you book your appointment — we'll check whether your car needs this.

Highly Recommend: Pair It With an xHP Transmission Tune

If your car has a ZF automatic transmission, we highly recommend pairing your MHD engine tune with an xHP Transmission Tune. xHP recalibrates the transmission control unit (TCU) to match your car's new power and torque output — firmer, faster shifts and better reliability under the added load from your MHD tune. Ask us about adding xHP when you book your appointment.

MHD Pricing By Platform

Every price below is for the license installed by Speed Logic with one OTS (off-the-shelf) map included, paid in-house at time of service. Ask about the MHD Wireless Adapter (+$100) when you book — it lets you flash on the fly from your phone, no laptop required.

Engine Platform	Compatible Models	Installed Price
Toyota Supra B58 (A90 / A91 Chassis)	Toyota GR Supra A90; Toyota GR Supra A91 (some ECUs need an ECU Unlock first — see above)	$600	Request Appointment
BMW S55 (F-Series)	M2 Competition, M2 CS, M3, M4	$600	Request Appointment
BMW S58 (G-Series)	M3, M4, X3 M, X4 M	$600	Request Appointment
BMW B58 (F-Series & G-Series)	240i & M240i, 340i & M340i, M440i, 540i, 640i, 740i, 840i, Z4 M40i, X3 M40i	$600	Request Appointment
BMW S63 (F-Series & G-Series)	M5 (F1x & F90 Chassis), M6, X5 M, X6 M	$800	Request Appointment
BMW N54	M2, M235i, 335i, 435i, 535i, ActiveHybrid 3, 640i, 740i, X3, X4, X4 M40i, X5, X6	$400	Request Appointment
BMW N55 (F-Series)	M2, M235i, 335i, 435i, 535i, ActiveHybrid 3, 640i, 740i, X3, X4, X4 M40i, X5, X6	$600	Request Appointment
BMW N55 (E-Series)	M2, M235i, 335i, 435i, 535i, ActiveHybrid 3, 640i, 740i, X3, X4, X4 M40i, X5, X6	$400	Request Appointment

Not sure which platform fits your car, or need help choosing between a license, maps pack, or the wireless adapter? Contact Speed Logic and we'll confirm fitment before you book.