[Healeys] HT ignition

Norman Nock sjnnock at sbcglobal.net
Thu Aug 28 18:04:36 MDT 2008


The HT spark from a points type ignition is low voltage when it is 
 compared to the very high voltage of the electronic HT spark ... 
the electronic spark is ALWAYS at its maximum HIGH voltage , but a points type ignition in dependent on how fast the distributor points separate , ie the faster the engine RPM the higher the HT voltage , upto a certain point 

THE HT SPARK can travel along the surface area of a insulator rather that jump the gap of a spark plug , so a rotor arm , a coil , distributor cap 
 have a large surface area to ground to prevent flash over to ground ,
the rotor for electronic ignition has a much greater surface area than a points type distributor OEM 

 If you need to see it happen pull off a spark plug wire with the engine 
running and see the spark jump out of the coil to ground ..

ELECTRICAL POWER LINES with VERY HIGH VOLTAGE HAvE BIG INSULATORS WITH VERY LARGE SURFACe Areas
             Norman Nock

More info. Healey Marque July 2006 OR my Tech Talk book page252
SURFACE AREAS


More information about the Healeys mailing list