The 4 pin GM HEI is designed to use 12 volts. No ballast resistor is required.

You could look it up.

One of the reasons that the GM HEI worked so well was that they used an E-core coil. The kind with the laminations on the outside. This let more of the energy get to the plugs.

I have posted about the E-core coil before. Price for a good one on Ebay is holding firm at about $12.00.

R.

Last edited by dogdays; 05/27/16 02:10 AM.