> The original design may actually have been just a tad weak in this area. If
> you approximate the distance through the middle of the rotor, from the
> contact arm to the center post of the distributor, I think it turns out to
> be the shortest route to ground found anywhere in the high tension system
> except for the actual plug tips. The other cars I've owned have been
> arranged to make this distance much larger.
>
> IMO the popularity of Lucas Sports coils and other ignition "upgrades" just
> aggravates the problem. Even the stock coil & points is capable of
> generating more voltage than it takes to jump the combined plug gap and
> rotor/cap gap; so effectively those two gaps limit system voltage no matter
> how much the coil is capable of. But, if there is a problem with the plug
> or plug wire; or if you run wider than stock plug gaps either intentionally
> or by not resetting the gaps as often, then the voltage rises until it is
> either limited by the coil/points capability or goes to ground somewhere
> else. If it jumps the path through the rotor to the dizzy shaft, then it
> will damage the plastic of the rotor, leaving a "carbon track" that will
> conduct easier next time. Eventually it becomes the easiest path to ground
> all the time, and the engine will no longer run at all.
Randall, do I have in my notes that you once suggested using dieletric goop
when mounting the rotor to confuse this tendancy to ground?
Terry
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