One of the most recent areas to go digital is electronic-ignition systems from MSD Ignition Autotronic Controls Corporation. - Super Chevy Magazine ...

That system consisted of breaker points, a condenser, and an ignition coil to store the current. Point timing had to tie in with spark timing via the distributor rotor indexing.

PerTronix’s Ignitor makes getting electronic ignition easy. We show you how, in around 30 minutes, to get rid of your old points in favor of a modern electronic ignition.

Unlike the other early Detroit electronic-ignition systems that used a fixed dwell time just as breaker points did, HEI increased the dwell period as engine speed was raised.