Pertronix 40111 6V 1.5 ohm

Your gap stays the same. Expect your points to burn up in short order with twice the amperage across them. Your link shows an oil filled coil.
 
Chuck Sea/Tac said:
What if you don't have points?
Click to expand...

You need to make sure your transistor ignition module is capable of (1) switching the peak amperage and (2) dissipating the resultant heat generated by the semiconductor voltage drop. The killer of ignition modules is generally #2. That heat is a function of the dwell times the number of cylinders divided by 360 then multiplied by the heat (watts) calculated by the amperage times the semiconductor voltage drop.

Doubling #1, the switching amperage, easily done by simply going from a 3 ohm to a 1.5 ohm coil, will instantly double the heat. That is why pertronix ignitor modules are NOT recommended for use with low ohm coils. They will fail, usually somewhere inconvenient, like on an elevated interstate cloverleaf with no shoulders.

A standard pertronix ignitor module (the black ones) will burn up in less than 20 minutes if you leave the key on with the switching closed (reluctor not rotating, equivalent to points closed) with a 1.5 ohm coil. You have effectively driven the dwell to max and the heat builds faster than it can dissipate.

If you want any sense of reliability with the 1.5 ohm coil use the ignitor II (red color, 12V only!) module.
 
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I was under the impression that 1.5 ohms (more or less) was the preferred resistance for a 6 volt coil? And 3 ohms for a 12 volt unballasted coil?
 
katy said:
I was under the impression that 1.5 ohms (more or less) was the preferred resistance for a 6 volt coil? And 3 ohms for a 12 volt unballasted coil?
Click to expand...





Yep.

One wants only 6v to the points regardless of battery voltage. [ no more than 8v with 12v battery]

So, the Pertronix 40111 is 1.5 ohm and epoxy filled. If 12v was to feed this coil a ballast resistor would be needed.

Thats my take unless I'm missing something.

And, to the original question. the sparkler gap can remain the same. .035"
 
I ran a Pertronix 40611 Coil with 12V for 200 plus miles without any abnormal degradation of the stock ignition points.
 
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