Where to get 12v for ready to run distributor

[redgum78]

I decided to replace the electronic ignition system on my 73 Chrager with a ready to run 12v distributor and coil upgrade kit.

So I need a 12v supply.
The easiest supply I could see is the run supply to the no longer required ballast resistor. Problem is it does not have supply while cranking. I have read elsewhere that it is ok to jump across from the 12v crank supply that bypasses the ballast while cranking.

Which is what I have done. I have a small jumper wire connecting the crank and run supply together and they now supply my new ready to run ignition. Seems to work fine (have driven it several times) and it appears there are others that have done the same.

My question is "is this ok?"

The more I think about it I wonder if feeding 12v back up the crank supply while the ignition is in run may cause an issue?

Anyone else here done this? Anyone know if this likely to cause any issues?

Thanks

[Nacho-RT74]

That' the way to do it.

Usually what ppl does is remove ballast and splice the wires together. Since i love the stock look and preffer to keep original stuff just in case you want ( for whatever reason ) get it back is modify the ballast. Remove the epoxy and resistor from the back and get a jumper wire in the groove. Seal it back and you will be getting a jumped ballast with a clean look.

If you want to get it to stock, just replace ballast without deal with a hacked wiring

[Nacho-RT74]

About an issue feeding back the cranking circuit for ignition... Don't worry, this circuit goes anywhere between ballast and ign switch. The contacts into ign switch just are closed while cranking. See it like this: the resistor IT IS ALREADY A JUMPER what links run and cranking always, just with a resistance

[redgum78]

About an issue feeding back the cranking circuit for ignition... Don't worry, this circuit goes anywhere between ballast and ign switch. The contacts into ign switch just are closed while cranking. See it like this: the resistor IT IS ALREADY A JUMPER what links run and cranking always, just with a resistance

Thanks Nacho, I was hoping you might respond  . I didn't actually think of the ballast as a jumper until you pointed it out. In a standard set up it would still be feeding resistor voltage back up the crank supply while ignition is in run wouldn't it?

Good idea on concealing the jump link in the old ballast. I might have a go at that tomorrow.

Thanks again.

[Nacho-RT74]

Yes, both circuits are feeded always, just one dimmed coming back from ballast while the other is getting full 12volts from ign switch

Aaaand that's why the brake light on cluster dims out while cranking, because this light is spliced into the run circuit

[redgum78]

 

[71ChargerMike]

I'm about to do a ready to run electric distributor system in my 71 Charger as well. Glad I came across this post because I was having a hard time finding a suitable power source and sounds like the ballast resistor is the best location. I can modify my old burnt out resistor to become a stock looking jumper for the new electronic ignition setup.