To answer some of the questions, the Coronet did have a working PVC and the breather fed into the air cleaner. Both engines run on pump gas.

The 383 internal condition is not known, but given all the leaks and other mechanical work on the car, it probably stinks. The car now has a fresh 440 in it. Have not done any tuning to it yet. Timing is 14/35 - both engines.

As far as my cousin's Pontiac 400, I do buy reversion, but why only on 4 cylinders? What does the blower have to do with it? We do know that we did have too much retard in it. It was probably high teens at full boost.