Hi All,
I'm looking to tidy up my engine bay, and, not having room for the ford 6 pot coil on the bulkhead, I'm thinking about converting to coil on plugs. I.E. linking the two paired coils in series, instead of the coil pack with three paired coils.

Providing the impedance of each pair of cops is the same as that on the ford coil pack, can anyone see an issue with this? better still, has anyone done it?

This drawing might make the idea clearer


EDIS with COPs

The only issue I can see with pairing in series, would be the possibility of if 1 coil fails, you lose its pair too

what ECU are you using ?

there are few that can run COP directly so you could do away with the EDIS all together....

Yes I thought about the failure aspect, guess I could carry a spare.

I'm running Megajolt with the EDIS, still on carbs, just thought, I should post on autosport labs too....

I don't think you're running them in series like you've sketched: Both terminals are positive and the COP is grounded through the engine. Looks more like a parrallel setup.

I've looked into a similar thing for an Alfa Twin Spark engine, these also need to have two coils fire at once.
For what I could find it's not a good idea to run both coils directly from an ECU output because they will draw too much current together.

One way do do this on a 4 cilinder engine, use a extra ignition aplifier:
http://www.microsquirt.info/Bosch_211.htm
http://www.bosch-motorsport.de/en-US/literature/en-US/Ignition_Module_IM_4_Datasheet_51_en_2778345099.pdf
Or use two of these for a 6-cilinder engine: http://www.bosch-motorsport.de/en-US/literature/en-US/Ignition_Module_IM_3.1_Datasheet_51_en_2778273675.pdf

You could also make your own from Bosch BIP373 modules:

This can be expanded easily to a 6-cilinder version.

Thanks Rost, thats really usefull.

So I'd just drive the spark a / b inputs from the edis coil outputs, adding a 'c' and L5 L6.

Guess I could also use two of those bosch units and 'waste' half of one.

Like I said before, you could use two of these:
http://www.bosch-motorsport.de/en-US/literature/en-US/Ignition_Module_IM_3.1_Datasheet_51_en_2778273675.pdf
They have three outputs. Don't know of any OEM part numbers though, but I guess they're findable on google