[Dave at Pelican Parts]

Wires: There should be four plugged into the coil.

There's the power wire to the coil, a thicker black wire (may have a red stripe or a faded red stripe). It gets plugged into the (+) terminal on the coil.

The tach signal wire is a thinner black wire with a purple stripe (often faded). It gets plugged into the coil (-) terminal.

Then the Pertronix has two wires, one going to (+) for power and one going to (-) to trigger the coil. I do not recall which is which.

Try unplugging the tach wire and seeing if that helps. Verify that the wires are plugged into the appropriate terminals. Verify the timing, as you will have changed it by moving the pickup around inside the distributor body. (That last is actually the most likely problem.)

--DD