MTFCA Forum

I am looking for any information on the wiring for using a Nissan twin spark distributor on a Bosch front plate setup. I have one of the distributors, the gears to reverse the rotation, and the front plate set up. It’s about time to get the thing together. Does anyone have a wiring diagram? Can I make it work with 6 volt?

There is this thread, noting two x 12v coils. What is the concern about 6v vs. 12v?

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Reno Speedster wrote: ↑

Mon Jul 21, 2025 12:49 am

Does anyone have a wiring diagram? Can I make it work with 6 volt?

Yes and yes. I'll try to draw one up this afternoon.

Charlie Yap had an article on the Nissan distributors in one of the Secrets of Speed Mags several years ago. You might contact him and get a copy of that edition. Not sure if the electronic module in those will operate correctly on 6 volts though! Quite possibly that might be an issue to be aware of.

Sorry, I was thinking points. With a Hal sensor, I would use 12 volts.

Sorry, I have been in the field for a bit and not checking. I want to keep a 6 volt system on the car and would like to keep points.

Points. You'll need two 3 ohms 6v coils and a 1.5 ohms ballast resistor. I'll draw it up.

(Your speedo cable shipped Monday).

The capacitor will probably need to be increased. Since coil inductance in Henry's is not published, we may have to experiment.

Great, thanks!

Okay Morgan,
All 6v coils seem to be 1.5 ohms primary, which make since. 6volts/1.5 ohms =4 amperes.

Two coils in parallel will give you .75 ohms load, so .75 ohms in ballast is required to limit the current to 4 amperes at 6 volts.

Standard motors VC-14 seem to be the ticket. They are blue now, but you can paint them black.

NAPA ICR-14 ballast rates at 1.4 ohms ,so that is about .7 ohms in parallel, giving a primary current of 4.14 amperes. A tad high, but on a 4 banger should be fine.

I drew in an optional shunt to bypass the ballasts at start, in case the starter draws the voltage too low for a quick start. I run a 6 volt system, and have not had a n issue, but with dual it may be an issue.

I have also shown a condenser diagnostic chart in case we need to change the condenser value.

Be advised with dual propagation, your peak cylinder pressure will occur sooner, so you will have to retard the advance to adjust for this.

Wow, thank you very much. I will do some study on this, but I warn you, I Al likely to have questions…

Not an issue. Jeff