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Twin plug firing and standalone management.

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Does anyone have any experience in fitting a standalone ECU to an engine with twin spark plugs? My OEM ECU fires the plugs sequentially, but to achieve that I would need an ECU with 16 ignition outputs which I'm struggling to find.

How would firing the spark plug simultaneously effect drivability and hp? Would piston crown design need to be change from OEM?

G'day M119K.

I haven't got any experience with twin spark engines that aren't rotaries, but would it be possible for you to move to a wasted spark setup, and halve the number of required ignition outputs?

Finding an ECU that supports twin spark with different ignition timings without a bunch of custom coding would be the next trick.

Are you referring to a Hemi or MB motor?

I recently did a KTM Super Duke 1290 V-Twin motorcycle engine that has two COP / spark plugs per cylinder. I was able to get the engine running just fine using a single plug or dual plugs firing simultaneously -- however, I had to use a separate ignitor (with two separate ignitor devices) for each plug in a single cylinder. If you wire both coils in parallel to one ignitor, then the current is doubled, and the ignitor limited the current before the coils reached maximum flux. Easy to see on an oscilloscope with a current probe.

Sometimes engines with a high # of output requirements are handled with two ECUs - one for each bank. Perhaps you could do that similarly for the second plugs, just use a second ECU with a second plug ignition map.