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I'm installing a Pertronix on my Boss, which has a repro mustard top coil. I checked the voltage at the positive side of the coil, expecting to have to bypass the pink resistance wire. The voltage read 12.12 volts, with the engine off. I know the coil is supposed to receive about 6 volts. I've searched quite a few Pertornixs postings, but didn't see an answer to my question. Am I looking for trouble (and in what form) if I leave the coil at 12 volts (ie., don't add the resistance wire)?

Carl
 

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Eventually, yes, you'll have problems with it, as that coil is not designed for a sustained 12 volts. How long until you have problems, depends on how often the car is used. If the car's not used that much, it could conceivably last quite a long time still.
 
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My understanding of Pertronix.

It needs 12 Volts to operate properly. If you are getting 12 volts at your coil, then you should be fine with the Pertronix. I had the same problem. I was getting the battery voltage at the coil. I hooked up pertronix and I'm not having any problems. I also installed a pertronix coil.
 

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I'm not sure if this has anything to do with your situation, but my understanding of the resistance wire for the ignition coil is that it should drop the voltage to between 6 an 9 volts while the engine is running. However, when you engage the solenoid to crank the engine over, a full 12 V is supplied to the coil from one of the posts on the solenoid until the ignition switch is returned to the run position. When you say 'the engine is not running', do you mean during cranking? If something else is going on, then maybe someone has previously altered your ignition wiring.
 

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Pertronix says minimum 8V at the coil + is what the ignitor needs to operate. The test to determine the voltage is to disconnect the pertronix and ground the coil - to the block and turn on the ignition. Use a digital multimeter to measure the voltage at the + side of the coil under load. Mine dropped from 12V to 10V with this test..
 

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you get +12 Vs because you have no current path thru coil with engine off and points (or equvalent) not gounding coil at place engine stopped. with points in and engine stopped with points closed you will get 6 to 10 volts generated by voltage divider action between ballast resistor (pink wire) and coil resistance. this is why if you leave ign in "run" with engine off you will heat up coil and eventually destroy it - that is why they have "acc" positioin on ign switch so you can play radio and turn on convenience lights without damage. with my pertronix in and motor running i get 9 volts and it has worked for 3 years. i never measured coil voltage with engine off but will do so and if you want results PM me.
 
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