12 volt question

Heres the deal, the OEM 6 volt coil is designed to operate on about 3.5 volts that is obtained by using the MANDATORY "infamous ballast resistor" mount on the backside of your dashpanel under the ammeter. Some 12 volt converters use the CHEAP technique of a 12 to 6 volt converting resistor AND the ballast resistor AND the square OEM 6 volt frontmount ignition coil. Done correctly, you should read about 3.5 volts at the coil terminal with the POINTS CLOSED and 12 volts battery voltage with the points open.

Myself, if'n I were to convert a frontmount ignition system to 12 volts, I'd use the newer square 12 volt ignition coil and NO BALLAST RESISTOR. You should read about 12 volts at the square coil terminal wheather the points are OPEN or CLOSED. (thats the way electrics work, trust me)

As a WAG, your OEM 6 volt frontmount coil PRIMARY winding resistance should read about 1 ohm and secondary about 7000 ohms. (note the MAJOR difference between primary and secondary resistances) The new 12 volt coil should read about 5 ohms primary resistance and again about 7000 ohms secondary. (again note the DIFFERENCE between the OEM 6 volt primary and the 12 volt primary) CAUTION: ohm meters are not accurate at low ohms reading (its a technical thing) but you should be able to discern the difference between the 6 and 12 volt primary resistance.

Actually, reading the coil terminal voltage is more accurate than reading the coil resistance (its a meter technical thing)..... ....Dell

jim

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My point was: DO NOT USE the "infamous ballast resistor" with the modern 12 volt frontmount coil.

My 2nd point was: pointing out the electrical circuit effects of distributed resistances, open circuits (points), and voltage readings. Kirchhoff's Law still RULES!!!

You need to fully understand the difference between the "infamous ballast resistor" and resistors in general. Not all resistors are ballast resistors but all ballast resistors are resistors with special characteristics. The infamous N-Ford ballast resistor is temperature sensitive and changes resistance depending upon its internal temperature which is governed not only by external temperature but also by coil current flow which automatically causes the ballast resistor to heat up.

The N-Ford's "infamous ballast resistor" was Ford's solution to cold temperature starting and inadquate 6 volt batterys. They didn't have "DieHards" in those days..... .....respectfully, Dell

Who does know how to convert to 12 volts the right way, and why.