EMS300 – Engine Management

$USD 200.0

SKU: EMS300 Category:


Standalone engine management system based on Megasquirt MS3x processor and firmware with enhanced inputs and output ports in aluminum sealed enclosure and sealed automotive grade connector. It is capable of controlling sequential injection on engines up to 4 cylinders, or semi-sequential up to 8 cylinders, combined with direct fire ignition for engines up to 4 cylinders (active or passive coils) or wasted spark ignition on engines up to 8 cylinders (active only coils). Can be connected as a fully standalone ECU or as piggyback and share the sensor reading with the stock ECU as it has differential trigger inputs, The 2.5 bar or 4bar internal MAP sensor can read up to 22psi or 44psi of boost,  5V ref voltage, on board jumpers to pull up resistors.  It has dedicated inputs (Crank, CLT, IAT, MAP, TPS and O2), 1 programabble knocking input. 10 low side outputs to drive injectors or any solenoid valve, 4 dedicated ignition outputs and to drive active coils (5v output signal),  5 digital/frequency. 4 analog/digital inputs. It comes with a mating connector and terminals. CAN bus connectivity, SD card slot and Real Time Clock (RTC) with backup battery for data logging. On board USB as main connectivity and external USB and bluetooth/WIFI as option.


  • 2x differential trigger inputs (HallVR).
  • 10x high impedance low side output  3A each to drive injectors or to be used for auxiliary outputs.
  • 4x ignition output gto drive active coils 5V output.
  • 4x inputs can be used as analog or digital (switch) input.
  • 5x digital inputs to be used for switching or to read frequency.
  • 4x dedicated analog input, coolant temperature, Intake air temperature,  O2 sensor, Throttle position.
  • 1x programmble knocking input.
  • 2.5 or 4 bar built in MAP sensor.
  • Fully compatible with MSextra Software
  • Fuel Table 16×16
  • Ignition Table 16×16
  • USB for PC communication.
  • CAN bus supported.
  • Mating connector and terminals.
  • BluetoothWiFi connectivity.
  • SD card logging (card not included).
  • Real Time Clock with backup battery (battery not included).
  • Can be connected as standalone or piggyback


Fuel table size 16×16
Fuel table resolution 0.10%
rpm resolution 1 rpm
Accel enrichment Simple (TPS,MAP), Enhanced (wall-wetting)
Spark table size 16×16
Advance resolution (commanded) 0.1 deg
Injector phasing Bank/batch fire
Fully sequential (up to 8cyl)
Injector timing Timed for start, middle, end of injection pulse
Injector trim Mapped trim table per cylinder.
Spark trim Mapped trim table per cylinder
Distributor spark Y
Trigger return dizzy Y
Simple wheel decoding Y
Every tooth wheel decoding Y
Wasted spark Y
Coil on plug Y
Dual dizzy Y
Cam / 2nd tach input Y
Number of spark outputs 8
Rotary trailing Y
HEI7, GMDIS Y (with bypass control)
Oddfire wheel decoder Y
Oddfire dizzy Y
Neon/420A Y
36-1+1 Y
36-2-2-2 Y
Subaru 6/7 Y
IAW Weber-Marelli Y
Mitsubushi 6g72 Y
4/1 CAS Y
4G63 (Miata) Y
99-00 Miata Y
Renix 44-2-2 Y
Twin trigger (aka. dual spark) Y
Suzuki Swift Y
Suzuki Vitara Y
Daihatsu 3 cyl Y
Daihatsu 4cyl Y
Rover K Series 36-1-1 Y
Rover K Series 36-1-1-1-1 Y
Rover K Series 36-2-2 Y
Honda VTR1000 12-3 Y
Chrysler 2.2/2.5 Y
GM 7X native Y
Nissan 360 tooth CAS SR20, RB25
Load methods SD, AN, map/baro (load%), MAF, ITB
Load blending Y
Load tables 2
Staged injection Y
Includes sequential staging and multiple banks.
Over-run fuel cut Y
Tachometer output Y
Launch Control/flat shift Y
Spark cut rev limit Y
Dwell duty% Y
Dwell battery correction table of %ages
Cranking pulsewidth table of %ages
Alternate cranking injection Y
Specific cranking advance, dwell Y
Fixed timing for setup Y
Test mode Pump, Inj, Coils, Idle
Closed loop idle control Y
Boost control Y (open or closed loop with PID control)
Nitrous control Y (2 stage progressive)
Knock sensor (software) Y
Realtime barometric correction Y
Water Injection Y
Table Switching Y
Configurable outputs Y
AFR target tables Y
Dual fuel tables (per bank) Y
Synchronous sensor sampling Y
CAN communications Y
Built in tooth/trigger loggers Y (tooth, trigger, composite, sync-errror)


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  1. When is the on-board wideband o2 controller going to turn on the heater circuit?
    After engine started or same timing as supplying 12V to ECU?

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