Distributor/coil
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Intermediate
Joined: Mar 2011
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Distributor/coil
I have a 72 vette, base 350 engine. I'm rebuilding the distributor (it wobbles and won't advance timing), and am installing a Pertronix II module in place of he point and condensor. I also want to put in a Pertronix coil. Here's my question(s): I have three wires coming off the positive side of the Delco Remy coil. One is for the ignition coil condenser (?), mounted at the base of the coil. There are also a red and black wire which disappear into a wiring harness. How do i tell if i have a resistor wire (I don't see a yellow wire), or a ballast resistor. And what wiring changes do I have to make to change over to the hotter coil?
All help appreciated. Thanks.
Windemere
All help appreciated. Thanks.
Windemere
Race Director
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First and most important you will need to fix the wobble and advance mechanism. The pertronix unit will not work properly with the wobble does not have it's own advance mechanism.
No C3 Corvette has a ballast resistor. The resistance is built into the wire leading to the + (positive) terminal on the coil.
Wire it according to this diagram
No C3 Corvette has a ballast resistor. The resistance is built into the wire leading to the + (positive) terminal on the coil.
Wire it according to this diagram
Thread Starter
Intermediate
Joined: Mar 2011
Posts: 27
Likes: 0
First and most important you will need to fix the wobble and advance mechanism. The pertronix unit will not work properly with the wobble does not have it's own advance mechanism.
No C3 Corvette has a ballast resistor. The resistance is built into the wire leading to the + (positive) terminal on the coil.
Wire it according to this diagram
No C3 Corvette has a ballast resistor. The resistance is built into the wire leading to the + (positive) terminal on the coil.
Wire it according to this diagram
Thread Starter
Intermediate
Joined: Mar 2011
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Safety Car
Joined: Apr 2006
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From: BC
I have the same problem. Stock 69 427 with ignition changed to petronix. Two cloth wires from ign. and starter to positive on the coil plus the red from the petronix module. One black wire (petronix) from the distributor to the negative on the coil and the capacitor/condenser is bolted to the coil bracket and also hooked to negative. Why is it still there?
Last edited by CanadaGrant; Feb 15, 2014 at 12:33 AM.
Team Owner
Joined: Sep 2006
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From: Westminster Maryland
Hi W,
The resistor wire does have the yellow woven sheath on it.
It and the black wire you mention both end in the same connector and that connector along with the black wire from the condenser are on the positive post. I'm not sure what color the wire is under the sheath.
The black wire running from the distributor's base is on the negative post.
Regards,
Alan
The resistor wire does have the yellow woven sheath on it.
It and the black wire you mention both end in the same connector and that connector along with the black wire from the condenser are on the positive post. I'm not sure what color the wire is under the sheath.
The black wire running from the distributor's base is on the negative post.
Regards,
Alan
Team Owner
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From: Crossville TN
The condenser attached with the coil is NOT an ignition condenser. The ignition condenser is mounted inside the distributor.
The one on the coil is a noise suppression condenser that attempts to eliminate ignition noises from the radio output. Leave it connected as it is, if you think that it's still functional. Otherwise, you can remove (or disconnect) it; there will be no effect on the ignition system.
The one on the coil is a noise suppression condenser that attempts to eliminate ignition noises from the radio output. Leave it connected as it is, if you think that it's still functional. Otherwise, you can remove (or disconnect) it; there will be no effect on the ignition system.
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Team Owner
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From: Crossville TN
The '69 Corvette came with a resistor wire running from the engine-side of the fuse block to the coil. It did not leave the factory with a discrete ballast resistor (like C2's and earlier).
Yours may need a separate ballast resistor if someone previously cut the resistor wiring off and/or replaced it with regular wire. But, if it still has the resistor wire, you can end up with a very weak spark if a ballast resistor is ADDED into the circuit.
(It would have been better to start a new thread with this question.)
Yours may need a separate ballast resistor if someone previously cut the resistor wiring off and/or replaced it with regular wire. But, if it still has the resistor wire, you can end up with a very weak spark if a ballast resistor is ADDED into the circuit.
(It would have been better to start a new thread with this question.)
Safety Car
Joined: Sep 2005
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From: Orange County Ca
I just remembered that my car origionally had a factory transistorized ignition--found the origional, disconnected unit when I was working on the front end.
So, maybe the resistor was origional for transistoried ignition cars? Or added later to make the standard points system work?
So, maybe the resistor was origional for transistoried ignition cars? Or added later to make the standard points system work?
Team Owner
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From: Crossville TN
The TI unit had a resistor wire with it, too. But, it was a different value resistance than for the points car. If the TI unit was removed, the resistance wire might have been, as well....or not. One would have to check the resistance of that coil 'feed' wire to know.
Team Owner
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From: Crossville TN
You would be best to call Pertronix to learn what they intended with their diagram. But, I would assume that the resistor in their drawing would represent any existing ballast resistor in the car's ignition system. This could be a discrete resistor like on C1/C2 Corvettes or 'in-wiring' resistance wire in C3 cars.
BTW, a resistance in that circuit is for limiting the amount of current that can be delivered to that coil during operation.
You should call Pertronix to be certain how their unit is to be hooked up. As I mentioned above, if you don't know whether the power feed wire for the coil is a resistor wire or not, just use an ohmmeter to find out. If you tell Pertronix folks what you have, they will guide you as to how to properly hook it up.
BTW, a resistance in that circuit is for limiting the amount of current that can be delivered to that coil during operation.
You should call Pertronix to be certain how their unit is to be hooked up. As I mentioned above, if you don't know whether the power feed wire for the coil is a resistor wire or not, just use an ohmmeter to find out. If you tell Pertronix folks what you have, they will guide you as to how to properly hook it up.
+1
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Can anyone tell me how long the resistor wire is? how far "back" from the coil will i have to go (ie cut open the wiring harness) to find the end of the resistor wire, if i need to remove and replace it so i can get 12 v to the ignitor module and the flamethrower coil? thanks.
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Two recommendations
1) don't cut the original wiring harness. Run a new 12V wire from a switched terminal on the fuse block
2) forget the flamethrower coil. It has a horrible reliability record and does nothing for performance.
1) don't cut the original wiring harness. Run a new 12V wire from a switched terminal on the fuse block
2) forget the flamethrower coil. It has a horrible reliability record and does nothing for performance.
Last edited by Mike Ward; Mar 9, 2014 at 03:33 PM.
