Ref/Sync Mode Help

[Ironhead]

I have a Motec M4e system in a BMW E30M3. For years I ran it with both ref/sync sensors, 4 coils, and sequential injection. Now for a variety or reasons I need to take a step back and run a ref sensor only with the stock distributor and group fire injection.

My problem is this. I have a 36-2 crank mounted trigger wheel, but I do not see a ref/sync mode that will allow it to run this way. Modes 1-4 apparently require "one tooth per firing" which I presume would be a two tooth crank trigger? All the other ref/sync modes seem to require a sync signal.

It seems to me that if the M4 knows the number of crank trigger teeth, and has the CRIP for the missing teeth, it would have all the information it needs to run with the 36-2 trigger (with batch injection and a distributor).

Or do I have it all wrong?

Any advice appreciated.

[AdamW]

Use ref/sync mode 81 or 83.
Set number of cylinders to 24
Set injector operation to 1
Set number of coils to 1.

[Ironhead]

Adam, Thank You!

I never would have deduced that on my own.

Engine at least fires with those settings, but it barely runs and is crazy rich, and throws out ref/sync errors. Since the fueling was tuned when I was running sequential, is there anything else related to fueling scaling that I need to change?

Thanks again!

[AdamW]

Did you try both modes 81 & 83? - If you are seeing errors I suspect it is triggering off the wrong edge. Try the other one.
Since injectors are now firing twice per cycle you need to halve your original IJPU (choose no when it asks if you want to interpolate the fuel table).