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feelsharp · 09-10-2012, 04:10 PM

No, if you wire it backwards you have reversed the coil polarity, it will over heat and fail. If you are actually using a 6 volt battery and the coil is marked requires external resistance, you will be ok. A 12 volt coil that requires external resistance is in essence a 6 volt coil. It will have around 1.5 ohm resistance. If it is used with a 6 volt battery you end up with the correct amps. With a 12 volt battery the coil must have added resistance totaling around 3.0 ohm to keep the amp load on the point around 3 amps. That resistance will either be internal with no external resistance required, or added by running your hot lead thru a chrysler resister.

09-10-2012, 04:10 PM	#3
feelsharp Member Join Date: May 2012 Location: Wadsworth, Ohio Posts: 36	Re: Using a 12 volt coil No, if you wire it backwards you have reversed the coil polarity, it will over heat and fail. If you are actually using a 6 volt battery and the coil is marked requires external resistance, you will be ok. A 12 volt coil that requires external resistance is in essence a 6 volt coil. It will have around 1.5 ohm resistance. If it is used with a 6 volt battery you end up with the correct amps. With a 12 volt battery the coil must have added resistance totaling around 3.0 ohm to keep the amp load on the point around 3 amps. That resistance will either be internal with no external resistance required, or added by running your hot lead thru a chrysler resister.