Ballast Resistor?

[GlenwoodCJ7]

During my rewire, I am trying to decide upon using the current ballast resistor from mallory (The ugly white one) or going with a ballast resistor wire. I am a little unsure of which to go with and which would do a better job of dropping voltage to the coil. My charging system already puts out a pretty high voltage at 14v and with the current resistor in place I can only get it down to 9.5. Anyone in the know about the wire?

 

[GlenwoodCJ7]

I've looked at the two side by side so to speak and looks like the wire from napa (Echlin product) has a resistance of 1.35 ohms and the mallory 700 has a variable resistance of .70-1.50. Kinda odd to me why you would want a variable resistance? Seems like your voltage would be a bit sporadic.

 

[GlenwoodCJ7]

Another question? I have a delco alternator and noticed that the 2 wire connection plug that has the red looping back to the batt terminal does not loop back, mine just runs tot he connector and stops. Why the need for the loop and what problems might it cause if not connected this way.

 

[69jeepcj]

What year jeep? Points or electronic ignition? typically a Ballast resister drops voltage to a points ignition from 12 down to around 9.0 so the points don't receive a constant 12 volts as that will burn up the points, the wire will do the same thing. Research from another jeep forum show ballasts have different resistances but do the same job. The variable resistance I would assume is to account for voltage spikes?? Not real sure on you alt, mine loops back.

 

[Dragon5126]

I've looked at the two side by side so to speak and looks like the wire from napa (Echlin product) has a resistance of 1.35 ohms and the mallory 700 has a variable resistance of .70-1.50. Kinda odd to me why you would want a variable resistance? Seems like your voltage would be a bit sporadic.

the adjustable ballast resistor is preferred. it doesn't get sporatic, you set it to the value you need and it stays there.

 

[Dragon5126]

During my rewire, I am trying to decide upon using the current ballast resistor from mallory (The ugly white one) or going with a ballast resistor wire. I am a little unsure of which to go with and which would do a better job of dropping voltage to the coil. My charging system already puts out a pretty high voltage at 14v and with the current resistor in place I can only get it down to 9.5. Anyone in the know about the wire?

The ballast resistor isn't meant to drop voltage, its job is to limit CURRENT so you don't burn out the coil. voltage divided by resistance (Ohms) equals current, 14 volts at one ohm (essentially no resistance) would be giving you14 amps flowing through the coil, which would burn it out in short order... the coil itself has a specific resistance above this so that isn't an issue, and the ballast resistor is simply a way to fine tune the intensity of the spark it generates at the plugs, it also helps lower the amount of radio interference generated by the ignition when you don't use carbon plug cables and resistor plugs.