voltage regulator

[HitIt]

Hey Meep, do you think a coil with a .6 Ohm resistance is too low for a stock ballast resistor? What's done in that case a different rated BR or take it out completely? Thanks.

 

[Meep-Meep]

Basically the lower the coil resistance (or impedance) the higher the current flow through the coil. Adding a ballast to the circuit will reduce the voltage and current flow in that circuit, which is required to not overload or over voltage some electronic switches like the Pertronix or Unilite - or burn points. Also to consider is the primary circuit operates on a duty cycle and not a constant ON condition so average current is dependent on how long the points are closed. When the points are closed for a percentage of time per revolution of the distributor cam (dwell) the coil draws current. To further illustrate the current draw characteristics of the primary side, 4 cylinder engines will typically draw more current because of the higher dwell angles so Pertronix will spec a different coil for that application. The coil is a transformer so increasing the primary voltage will get an increase from the secondary side, so running without a ballast will produce a hotter spark but at the expense of the trigger mechanism. In 69runner's case it sounds like he did some homework and selected components that handled the higher charging voltages and additional current draw.

As for specific coil impedance information you will have to check with who made the ignition module. Again, selecting the proper coil and ballast will protect the trigger circuit (ignition module) from over current.