Megasquirt Assembly

Building the MS: fix this shit its not right DOSE NOT WORK

I've taken the liberty to remove from the component map what you don't need to install to make this very simple and straight forward.

But please refer to for the step by step instructions and tips on building the megasquirt.


The above components are all you'll need to run the majority of MS installs. I have removed the injector PWM circuit (used to drive Low-Ohm injectors; cannot be used with Hi-Res code) and the VR tach input circuit, which we don't use.

Be sure to jump with wire:
D1 & D2
XG1 to XG2
TachSelect to OPTIN

Once you finish installing your components, you need to mod the board for your tach input and spark output like this:


It has been noted that you can replace the two 1K ohm resistors (for the spark output) with 100-470ohm resistors to increase the power to your coils for a better spark.

How it's done:


NOTE I built my harness different than I posted above, notice my spark outputs are crossed, do not follow that unless you have good reason to.

Tach input filter:

To eliminate noise/interference on the tach input we install a .1µF capacitor on that circuit as a filter. This eliminates random misses and allows you to use Hi-Res code successfully.

Solder the capacitor between JS8 and Ground, you can see this in the diagram below.


Onward to your mods!

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