Sorry I arrived late, but as an electrical engineer I love this sparky chat......A couple engineering points.....
1) I AGREE WITH JIM (janicholson) the location of the ballst resistor DOES MAKE A DIFFERENCE which is why factory set ups ALWYAS had the ballast BEFORE the coil NEVER between it and the points YUKKKKK. Sure its a series LR circuit when the points are closed and at steady state during that time the condensor is shorted out by the closed points (LR ONLY),,,,,,,butttttttt when the points open then its a series LRC circuit and theres ringing and oscillation occuring between the condensor and coil (thats just an LC circuit mostly) until its all damped out i.e. the condensor charges up and stores energy but then it gets discharged (back into the coil), (Ive seen oscilloscope prints of that action). In the factory wiring the coil and condensor are next to each other in series with NO RESISTANCE BETWEEN THEM (its BEFORE the coil remember) any resistance between them (when the ringing oscillation occurs) would serve to discharge energy in the form of wasted heat versus it getting fed back direct to the coil where that energy gets transformed into magnetic energy storage and transfer over to the secondary and out to the plugs where it does more good then the ballast wasting it as heat.
2) THE COIL POALRITY WIRING INDEED ALSO MAKES A DIFFERENCE Why you think the factory bothers to label those lil terminals + and - ??????????. Its easier to discharge electrons from a hotter surface (plug electrode) to a relatively cooler (plugs ground strap) surface. Thats why in vacuum tubes theres a heater located under the cathode to HEAT IT UP to easier emit electrons up to the cooler non heated plate. A retired physicist friend of mine actually took measurements of firing voltages when coil leads were correct but then reversed and found it was several thousand volts less if the coil was wired correct. i.e. if at reverse polarity the coil has to work harder and heats up more and is less efficent becasue it takes more voltage to arc jump the gap if the electrons have to flow from a cold to a hotter surface. SURE she still sparks either way butttttttttt its more efficient and the coil wastes less energy in heat if its wired at the correct polarity.
DISCLAIMER hey its IMPOSSIBLE to explain the Kettering coil ignition system in a few sentences here as that takes entire books and years of study to accomplish, so the above is wayyyyyyyyyyyyyy over simplified and perhaps not 100% perfect but its how I best recall it works and WHY THE BALLAST GOES BEFORE THE COIL AND THE COIL POLARITY MAKES A DIFFERENCE. I graduated from Purdue EE in 1969/1970 so Ive slept some since then lol but this is my ebst effort to help yall (especially non electrical engineers and technicians) understand
God Bless yall for your help here
Ol John T BSEE,JD in Indiana
PS My Ignition Troubleshooting may also help the original poster
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