[Healeys] Coil Terminals

[Richard Ewald]

>>Is there any way to distinguish a positive ground coil from a negative
ground coil?  I should look to see if there are any part numbers stamped on
it anywhere.

There is a real easy way to tell if the coil is wired correctly.  Hook the
engine up to an ignition oscilloscope.  If the coil is hooked up backwards
the real pretty squiggly lines will be upside down.
The engine will run if the coil is backwards.  In fact you probably would
never notice the difference if you wire the coil backwards.  The reason for
the polarity is that firing backwards it takes about 15% more energy to fire
the plug than firing forward.  So as long as your power requirements are
less than about 85% of the coil's output you will probably never be able to
notice the difference.

Rick