I've had a Pertronix Billet distributor in my car know for several years. Sometime last year it started having random ignition stutters where the car would die for a split second then run OK again. There was really no rhyme or reason but tended to happen at lower RPM's. It seemed to be getting worse so I worked on it tonight. I assume the ignition wire going to the coil has a resistor. With Key ON and Ignition off it would get full 12.5 volts or so. With car idling it would only get 11.5 volts. As engine RPM went up ... Voltage went down ... a high rev would drop it down to like 7 or 8 Volts. Is this what a resistance wire does? Anyway I move the Pertronix wire from the + COIL connector to FUSE 4 in the fuse panel. This gets a full +-13V during crank and engine running at any RPM. Gonna take the Grabber for a test drive tomorrow and see if the problem is resolved. For those that have a Pertronix ... should the coil also be rewired to get a full 12V all the time? Or is it OK for the voltage to drop as RPM's go up? It is a Flamethrower II coil and a Ignitor II Pertronix ....
I would think with any electronic ignition system you will need a full 12v to your system .This the way I have wired all my converion in the past. Jay
the primary reason for the resistor wire was so that the points would not burn out as fast. the stock coil is intended to be used with the resistor wire. if you replace the coil then get a 12v source for it.
I'm no expert, but from what I know, Bryant is right. The pertronix works better with a full 12volts, and the coil will too. I'm still running points, and I'm not sure if my car had points or was a Duraspark, but I have 12Volts running to my coil at all times. I may have to replace the points more often, but no more than it's driven, that's no big deal for me. Mine developed a stutter simular to what you are describing a while back. I opened the hood lat one evening, just before dark, and spotted my problem-the vacuume line for the advance that has one of those braided covers on it was actually shorting the coil every once in a while! The coil lead was out of the dizzy just a bit...spark was jumping to the vacuume line. Moved the vacuume line and reseated the coil wire, problem solved!
OK ... after driving around today for a while the stutter is gone so it was definitely the Pertronix having problems on the resistor wire - why it took so long to show up I have no idea. The coil seems to be working fine on the resistor wire .. although I am sure the spark is not as hot as it could be. Gonna give Pertronix a call tomorrow and verify 100% .... Thanks guys ...
I did some reading on mine last year, from what I found on their website, they will work down to 8V. Maybe the resistive wire is breaking down? or are you still using the factory plug up by the firewall? Could be a bad connection there? Good to see it's working again.
I'm using the factory wiring to the coil ... maybe the factory resistance wire gets more resistant with age???
From the problems I have read about the Petronics' the coil has to be matched to the module in the Distributor and the voltage feeding the coil has to be right per the coil. I probably have this wrong but I have read where several people over the last several years are starting to have problems with the Pertronic coils going bad on them. I helped install one on a friend's 66 F100 and about a year later the coil went bad. After looking at the Pertronic directions I found them very confusing about what coil is needed with what voltage. Some say use a resisitor and some don't need them but it was cofusing on which was which. I do know that if the wrong voltage is used with the wrong coil it will go bad after a while. Clint
Talked to Pertronix Tech Support. They said ideally both the coil and Ignitor II should be running off of 12V not the resistor wire. I explained to them that moving the Ignitor to 12V fixed my stumble problem and I left the coil on resistor wire. The technician said that unless I'm using the setup on a high RPM racing Engine I more than likely would not even notice a difference moving the coil to 12V and can probably just leave it as is on the resistor wire.
I think part of the trouble people have had wit them was with the Igniter I not the II. They tried running the coils off 12v and burnt them up. The Igniter II supposedly takes the 12v. Glad you go her figured out. clint
