Your answer(s) lie(s) with you. Your unique engine, assemblage of parts, how they interacted with each other. You would have had to check endplay of the cam, how the dist/pump gear meshed with the cams gear, etc etc.
You would have to agree it’s not a one size fits all answer. If you checked and verified during assembly “maybe” you would have seen something. Maybe not.
Did you put it all back as it was and recreate to see what goes on? Only you can find the answer.
