This has been discussed here before.
The Mallory distributor was not mentioned by anyone as having that issue. Neither have the newer MSD units.
This would tend to explain why the MSD 6a isn't firing also. It isn't seeing the on/off signal from the distributor to make the coil charge and discharge. So you still need to verify that after you change the distributor out.
Avoid "rebuilt" distributors of any kind. Including the Ford/Motorcraft and any of it's variants.
The ONLY common denominator with pin failure in them, is that someone else has had them disassembled after they were build new.
Unfortunately there is no way to check the quality of roll pins. I haven't looked but maybe ARP list some? I would feel comfortable with that.
As I said, I am running a "Ford MotorSPORT" 341A "racing" distributor. It is a double pinned gear.
Agreeing with others here too, get rid of the "coil in a can" coil. Go to the newer coils.
Agreed on the location of the distributor. This is one time that a GM/Chevy would be helpful.
The "MSD Ghost of Christmas Future" is visiting you now. Ask him as you look at your name on the gravestone, "is this something that WILL be or is this just something that MIGHT be?" The MSD Tech Support will never answer that question. Screw them.
You can call Jon Haas ANYTIME and bug the crap out of him. His Pantera-Electronics ignition even works with the silly coc-a-mami Mallory distributor that HE runs? Huh! Go figure?
(psst: tell 'im I sent ya!
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