Quick Links

MegaSquirt 3 EMS System V3.57

MegaSquirt 3 EMS System V3.57



Frequently purchased together

8' MegaSquirt Wiring Harness (MS1/MS2/MS3 Ready)

DB15 Pigtail Harness

USB Tuning Cable for MegaSquirt-III/ MS3Pro 1st Gen

SKU: MS3357-C_BL Category: Tags: , , , , , , , , Brand:


Important Note:  Due to supply chain challenges and the lack of ability to have parts anodized at this time, we are transitioning to brushed silver enclosures.  We appreciate your understanding.  

MegaSquirt 3 Engine Management System w/PCB3.57 – The MegaSquirt 3 is a drop in daughter card that greatly expands the MegaSquirt’s functionality. This model is equipped for basic, batch fire, but can be expanded to add sequential injection and 8 channel ignition control with an MS3X card (sold separately). Advantages include loads of additional processing power, speed, and features over the existing MS1 and MS2 systems. The MegaSquirt 3 daughter card alone provides these features and more:

  • VE and ignition tables are now both 16 x 16
  • 0.1% steps on VE table, 0.1 degree steps on ignition table
  • Socket for an onboard SD card – no laptop required for data logging  (SD Card not included)
  • Built in USB port
  • GM stepper IAC control
  • Closed loop idle and mixture control
  • CANBus communications for interface with GPIO Board, IO Extender, or other devices
  • Staged injection
  • Native support for many different OEM trigger patterns

Ready for two fuel outputs and one 5V logic level spark output. The MegaSquirt 3 also gives you a starting point for even more expansion. Further expansion with MS3X enables features like:

  • 8 channels sequential fuel control
  • 8 channel sequential ignition control
  • Individual fuel and spark trim for cylinder by cylinder tuning
  • 2 and 3 channel PWM IAC control
  • 2 stage nitrous controller
  • Table switching for multi-fuel engines
  • 2 step launch control

For complete MS3 documentation and more see

Customer reviews


There are no reviews yet.

Only logged in customers who have purchased this product may write a review.

What harness do I need with this?

  • You need only the MegaSquirt (MS1/MS2/MS3 Ready)  harness.

What inputs and outputs is the MS3 V3.57 set up for?

  • It is set up for basic fuel control and single channel logic level spark output, with the following inputs and outputs:
    • Coolant temperature
    • Air temperature
    • MAP sensor (built in)
    • Throttle position sensor
    • O2 sensor – narrow band or external wideband controller
    • Single RPM input – Hall, optical, or VR
    • On/off, stepper, or PWM idle control – unused idle control outputs can be repurposed as general purpose relay control outputs
    • Fuel pump relay
    • Two fuel injector banks
    • One 5 volt logic level spark output
    • CANbus

What firmware does it have?

  • The MS3 V3.57 ships with the latest MS3 code. The code it initially shipped with will be indicated on a sticker on the underside of the unit.

Is the V3.57 board available in kit form?

  • The V3.57 is essentially a V3.0 that has been changed for machine assembly with very few differences. Consequently, it is not offered in kit form.

What connections are on the DB15?

  • By default, it only has a couple extra reference voltage and ground pins for sensors. The DB15 can be used for adding optional I/O if you run out of pins on the main connector.

Where is it built?

  • The components are assembled at various locations in the US, with final assembly completed in Gainesville, Georgia.

What is the warranty?

  • We provide a one year limited warranty against manufacturing defects.

Questions & Answers

    Hi folks. Do you have a handle on the odd Subaru 6/7 crank trigger or would I have to switch it out for the WRX unit? I'm planning to run this on a 93 Subaru 2.2L turbo car. I bought a Micro squirt awhile back, but couldn't find any long term success stories. Got a lot of negative feed back from my Suby crowd, so I sent it back to you. I'd be will to try the MS 3, if it will work for me with out too much headache. Thanks. Steve.
  1. 0 votes
    Q Hi folks. Do you have a handle on the odd Subaru 6/7 crank trigger or would I have to switch it o...... Read more
    Asked by Steve Webster

    Yes, this is supported. You may need to adjust the VR trim pots on the MS3X to get the right amount of noise filtering for the cam signal.

  2. Is the MS3 compatible with a ford EDIS system and do i need the module to run it?
  3. 0 votes
    Q Is the MS3 compatible with a ford EDIS system and do i need the module to run it?
    Asked by Hugh

    The MS3 can run an EDIS type ignition with or without the module. If not using the module, you will have a much easier time using the MS3X; an MS3 without MS3X will need considerable modification, while adding the MS3X gives you eight spark outputs out of the box.

Only registered users are eligible to enter questions