That's OK because the HEI will retard with RPM too. You can't see it with a timing light but you damn sure see it with a good distributor machine. That's why locking out the timing is a bad deal.
Would it worthwhile to screw in as much timing it takes to make it detonate, then pull it back some? Seems like a light becomes pretty useless if the ignition is retarding on it's own at RPM.
