Pertronix coil question
Thread Starter
Team Owner
Joined: Jul 1999
Posts: 26,545
Likes: 46
From: Huntersville NC
Pertronix coil question
just did a search on "ballast resistor" and there are relevant threads but didn't exactly answer my question.
I have a 68 L-36 (427/390), About 5 years ago I tried a Pertronix module and flamethrower coil. The module lasted about a month and I went back to points, which I like. I kept the flamethrower coil, and have been running this with points for the past 5 years.
I have been running the flamethrower coil with points and no ballast resistor. I just want to clarify, that if I change the coil back to a stock style coil, I will also need to add a ballast resistor, won't I ? I am chasing some high rpm hesitation which I think is fuel delivery, but I would also like to rule out the possibility of ignition problems. What are the symptoms of a coil going bad? Thanks.
I have a 68 L-36 (427/390), About 5 years ago I tried a Pertronix module and flamethrower coil. The module lasted about a month and I went back to points, which I like. I kept the flamethrower coil, and have been running this with points for the past 5 years.
I have been running the flamethrower coil with points and no ballast resistor. I just want to clarify, that if I change the coil back to a stock style coil, I will also need to add a ballast resistor, won't I ? I am chasing some high rpm hesitation which I think is fuel delivery, but I would also like to rule out the possibility of ignition problems. What are the symptoms of a coil going bad? Thanks.
Melting Slicks
Joined: Mar 2005
Posts: 2,838
Likes: 10
From: Austin TX
If you're running points, you really need the coil that's designed to run on 5-8v, which means that either a resistor wire or ballast resistor is used to the coil. The points will fry with a full 12v,..I've seen them literally weld themselves shut.
Don't run 12v to a coil designed for 5-8v (a stock coil for instance) or you'll burn up the coil.
If you're running the Petronix kit, run the 45,000v Petronix coil which needs the full 12v input.
Confused yet?
Don't run 12v to a coil designed for 5-8v (a stock coil for instance) or you'll burn up the coil.
If you're running the Petronix kit, run the 45,000v Petronix coil which needs the full 12v input.
Confused yet?
Burning Brakes
Joined: Sep 2005
Posts: 1,078
Likes: 0
From: Santee CA
Visit your local Mallory parts distributor and get a Mallory Ballast resistor.
I did quite a bit of study on this when I had to change our old Lucas distributor on our Jaguar (the old one self destructed and we would've had to buy a used one to replace it) to a Mallory pointless distributor, and we had a Pertronix coil on it as well.
All documentation with the Mallory distributor and the Pertronix coil said to use a ballast resistor; go with one.
I did quite a bit of study on this when I had to change our old Lucas distributor on our Jaguar (the old one self destructed and we would've had to buy a used one to replace it) to a Mallory pointless distributor, and we had a Pertronix coil on it as well.
All documentation with the Mallory distributor and the Pertronix coil said to use a ballast resistor; go with one.
Thread Starter
Team Owner
Joined: Jul 1999
Posts: 26,545
Likes: 46
From: Huntersville NC
Originally Posted by 73, Dark Blue 454
If you're running points, you really need the coil that's designed to run on 5-8v, which means that either a resistor wire or ballast resistor is used to the coil. The points will fry with a full 12v,..I've seen them literally weld themselves shut.
I have been running this way for at least 5 years and maybe 7k miles. As I said, I installed the pertonix flamethrower coil and the pertronix ingnitor I, then removed the igniter and went back to points about 1 month later. When I put the points back in I kept the flamethrower coil. Think I will check the points. Might replace the coil also. So if I replace the coil with a stock coil I also need to wire in a resistor, si?
Racer
Joined: Jan 2004
Posts: 263
Likes: 1
From: 20,000 leagues under the sea
Are you still using the original wire from the starter to coil? If I remember right it is a yellow cloth covered wire that has the resistance as part of the wire (not a separate resistor). If not than I would also say you would want to put in a ballast resistor. You should be able to check the voltage to the coil (with key on, engine off) to know for sure.
Burning Brakes
Joined: Sep 2005
Posts: 1,078
Likes: 0
From: Santee CA
Originally Posted by 68raggtop
Are you still using the original wire from the starter to coil? If I remember right it is a yellow cloth covered wire that has the resistance as part of the wire (not a separate resistor). If not than I would also say you would want to put in a ballast resistor. You should be able to check the voltage to the coil (with key on, engine off) to know for sure.
Whoops, I forgot about the resistor wire on the Vette...Of course, if the car's old, and the wiring's brittle, might be a good idea to replace it with a new ballast resistor.
Thread Starter
Team Owner
Joined: Jul 1999
Posts: 26,545
Likes: 46
From: Huntersville NC
Originally Posted by 68raggtop
Are you still using the original wire from the starter to coil? If I remember right it is a yellow cloth covered wire that has the resistance as part of the wire (not a separate resistor).
But there is one thing that doesn't make sense to me. I understand that a stock coil is not made to handle an input of 12 volts and that 12 volts IN will harm a stock coil. The part I don't understand is that the flamethrower coil is supposedly putting out 40,000 volts, so wouldn't that fry the points either way, if they were going to get fried?
Safety Car
Joined: Jun 2004
Posts: 4,653
Likes: 80
From: Lakeland Florida
Hello,
Sorry to interrupt or hijack this thread, but I have a similar question. I have installed the Pertronix HEI conversion kit on my 73. I am keeping the stock coil, and am replacing the points and condensor.
I looked all over my engine compartment for the ballast resistor, and could not find one. Isnt this supposed to be a ceramic block about 2 inches long, and 1/2 in wide? The car is a 73, and I checked in my AIM manual, and my Chiltons manual. I could not find any resistor in the path. Is it only a matter of checking out the coil and measuring the resistance that will determine if you need the ballast resistor or not?
kdf
Sorry to interrupt or hijack this thread, but I have a similar question. I have installed the Pertronix HEI conversion kit on my 73. I am keeping the stock coil, and am replacing the points and condensor.
I looked all over my engine compartment for the ballast resistor, and could not find one. Isnt this supposed to be a ceramic block about 2 inches long, and 1/2 in wide? The car is a 73, and I checked in my AIM manual, and my Chiltons manual. I could not find any resistor in the path. Is it only a matter of checking out the coil and measuring the resistance that will determine if you need the ballast resistor or not?
kdf
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