I wanted to end this thread with what could be useful information to anyone else wanting to use a TI distributor to trigger an MSD box. After an exhaustive look through the internet and calls to Dave Fiedler, (TI expert), and Peter Serio, (also an electrical and instrument expert), there is no answer yet. But I know how to find it at least. I found an obscure tech bulletin from MSD that addresses the issue and why the polarity matters. It has to do with what MSD does with the signal from the magnetic pick-up coil. One of the pick-up coil wires is grounded inside the MSD box. The other lead goes to a power transistor to trigger the MSD. The only way to know if the polarity is correct for sure is to test it on a running engine. Hook it up one way and set the timing to some number, say 10 degrees. Then reverse the two leads on the pick-up coil. Start the engine and look at the timing now. If the timing is more advanced than it was the first time, say 25 degrees, it is WRONG NOW. Change it back the way it was. If it is retarded now, it is correct. Leave it as-is and readjust the timing. This would be correct for all MSD Boxes that are analog type like a 6AL. If you are running an MSD digital box, the results need to be reversed. You want the pick-up coil to be the most advanced. Why is this? It has to do with the logic in the MSD boxes. You have to remember the pick-up coil produces an AC sine wave. The analog boxes trigger off the trailing edge of the wave and the digital boxes trigger off the rising side of the wave. Hope this makes some sense. Once I get all this in the car, I will post up what wire colors do what and that will end the story.
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