The resistor concept is no longer used on HEI and Similar systems because they do not use "Oil Filled" coils.Some of the Prestolite and Motorcraft systems that use "Oil Filled" coils still use resistor but it is incorporated in the Coil it's self or the Control Module. Accel,MSD,and Mallory still have coils availble that are "oil Filled" and all the ones I have used still require an external Resistor unless they are being used with one of thier control boxes. Away maybe this will help clarify some of the " Spooky Stuff" for the newer guys...Paul
