Dual plug heads / coil choices
 

I have a '78 Shovelhead chopper with dual plugged heads.

I am running an Ultima single fire/single coil setup on one set of plugs. (The Ultima equipment appears to be 'very similar' to the Dyna 2000i module and coil kit). It works great btw.

The coil resistance is 2.4 Ohms and the voltage output is around 45000V, apparently.

I would like to add a second ignition coil to the setup in order to have all four sparkplugs running.

My question is: If I purchase an additional single fire coil with the same outputs and resistance will this work, or do I need to purchase coils with a lower resistance in order for the single fire setup to run properly across all four plugs?

Informed answers very gratefully received. Opinions about "why you don't need to bother with dual plug", less so... :icon_wink:

We always used one coil [not the popular 2 in one for single fire] coils... one typical coil for front and one typical coil for rear... simple shit..
typical= old fashioned electronic ignition [3 ohm] dual tower coil...

Run 3 ohm Dyna coils...... on a single fire crane hh / SS...https://cimg4.ibsrv.net/gimg/www.hdf...9e47e1e43.jpeg
https://cimg5.ibsrv.net/gimg/www.hdf...de22b5a95.jpeg

Good coils certainly...and Typical IMO
But, the Electronic ignition OEM Coil is just fine also.. Ain't racing I presume... no need to be Pretentious..Just light the fire.
Tho if Very high Compression and high RPM.... Better coils are a better bet...

Yep those Dyna coils are a bit pricey . Lucky you might find used but bring your ohm matter with yah.....

Yes there is that... Even replacements, could be used... Note that the newer O.E. Electronic ignition Coils, have EI or some such printed right onto them...

Coils
 

Does anyone know how I can use 2x singlefire coils with 3 terminal posts for a dual plug setup?

The coils recommended (which I am aware of) are 2 terminal post.

https://cimg0.ibsrv.net/gimg/www.hdf...18656b892a.jpg
The bottom image is the setup I am running. Is it possible to buy a second coil and run it in tandem.

The Twin coil setup in the top image is ‘standard’ and I would like to do something different.

^^ Go Ahead... must wire in parallel, which means the Ohms is less ... may burn up the iggy unit... but, that is the cost of "Different"
Personally i do Not believe in re-inventing the wheel...an age old design, that is still highly functional... tho Boring!!!