The greatest differences can be found in an efficient module and the self-contained coil, which is capable of putting out much more power with less dwell time.

Attach the spark plug to a spark plug tester, then connect the tester to the ignition wire. Start the engine and observe the ...

The HEI’s integrated ignition coil in the distributor cap makes it the most compact ignition system in history. No external ignition coil to sweat out.