MSD and Ballast Resistor

[mikiec]

Is there a reason that a ballast resistor is connected in an MSD system.

The system includes msd dist. 6al module and msd coil.

One of the AZ Cobra members encountered a problem ober the weekend. His fan quit. He found a hot lead coming of the ballast resistor and connected the fan to it. Car ran for about 40 seconds then quit. The ballast resistor was changed but still no fire. No power to coil at all. I have no idea why the resistor was left in the system.

Owner had the car chamged over to the msd system a couple of years ago.

Mike

[HighPlainsDrifter]

Hi,
The ballast resistor is only used in a points system.
The white lead from the msd box is for the points trigger, if it's a magnetic pickup then the white lead isn't used.
Perry.

[mikiec]

Perry,

Thanks. That's what I remembered as far as the points system is concerned.

I just do not know why the resistor is still in the system and is being used. I forgot how hot they can get.

What was interesting is that the people that re-did the ignition system left it there and added an additional spade to the hot side of the resistor. I think that's where they supply power to the MSD box.

Most confusing.

Thanks,
Mike

[HotRodJoe]

I think MSD 6A box has internal resistor for coil (no need for ballast).

Joe

[viking]

Running the ballast won't hurt a thing, the Pertronix magnetic pickup IS wired the same as points, one thing they overlooked in the MSD & Pertronox instruction books, took awhile to figure out but has been working fine (with ballast) for almost 3 years .

[Steve R]

I have a MSD tech sheet that says you should not use one. If you want, I will scan and post it.
Steve

[SCOBRAC]

I left mine on. I pull power off it to the small red wire. To be honest I forget why except It wasn't hurting anything and it was a good way to retain the original "look".

[mikiec]

It appears that the MSD6AL failed.

Mike