Okay Lee . . .

I'd never heard of this HEI phase 'flaw' before - but then again I have always been a spectator when it comes to racing - but I do like to read about the concepts that make certain feats possible . . .

Correct me if I am wrong, but I think that I understand what distributor 'phasing' means:

Regardless of how the spark is set free from the coil (breaker point(s), or HEI trigger) the juice doesn't flow in an instant. It takes time to build and it tapers off.

For this reason the juice for the spark should be set free when the rotor tip is just aligning with the leading edge of the cap conductor - and should rise and fade as the tip slides across the cap conductor face. If the breaker points close or the trigger fires to early or late it impacts the quality of the spark at the plug and may even create burning and pitting on the rotor tip or cap conductor. So out-of-phase is early or late in this alignment; a condition that is most notable at high RPM when time and distance get very compressed in the geometry of a distributor.

regards,
stock49

[Linked Image from 49fastback.com]