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Old 07-08-2012, 10:44 AM
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You want to run a coil and ballast if necessary, to achieve a 4 OHM resistance across both.
If you have a coil with a 2.5 OHM primary circuit, add a ballast of 1.5 OHMS to achieve 4 OHMS.
4 Ohms divided into 12 volts is 3 Amps. Thats pretty much what a points setup is capable of running without burning up points. AND seeing how the pertronix is a points REPLACEMENT then you need to keep in line with what the points would be using.
If you want High Energy Ignition, use a magnetic trigger style dizzy and an MSD or GM HEI Module mounted to a heat sink. They can run a lower Impedance coil, like 2.2 OHMS.. and 2.2 OHMS divided into 12 is about 5.5, which is what the GM HEI will comfotably run at. From what I have read ,the GM module limits current to about 5.5, if you run a lower impedance (resistance) coil it wont hurt it as the current limiting part (called a darlington) of the module keeps it at about 5.5 amps.
Fact is stranger than Fiction

Last edited by LATECH; 07-08-2012 at 11:11 AM.
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