MicroSquirt.com read only forum (Jan.15,2018)

I have a Goldwing 1500 6 cylinder (boxer) for which I want to use the negative coil wire as tach signal. I am using the megasquirt V2.2 and have 2 throttle bodies, each with one injector.
The engine has 3 coils (1 for each pair of cylinders) and is firing one coil each 120 degrees.
I did attach the tach signal to one coil on which I could start and run the engine. My fear is that 2 squirts per engine cycle is too little. Therefor I tried to hook up the other coils to the tach signal, but here I get stuck.
I am not that familiar with electronics, but I know this has to be done by using diodes. I tried a wiring diagram I found in the MSN-extra description to hook up multiple coils for the tachometer. This diagram is using one zener diode (3.3 v) and for each coil a normal diode (1N4004). I tried this, but without positive result. Is there anyone out there who can help me with a schematic how to derive the tach signal from 3 coils?

I would try using one coil and pretend you have a 2 cylinder engine. Provided the rpm is displayed correctly it doesn't really matter seeing as you are fuel only.

James

This is exactly the condition I'm running on now, but as it's a 2*3 cylinder I want to have at least 3 squirts in a cycle, and if possible 6.
I'm worried about running some cylinders too reach and some too lean.
Do you have any experience with TBI and do you think it really matters ?