There is a blog titled "MOTOR OIL ENGINEERING TEST DATA" here by a mechanical engineer wherein he tests over 250 different oils and discusses many topics.

One article is "Here is what you should follow for a successful start-up of a new rebuild of a traditional pushrod flat tappet engine.:"

Another is "STD VOLUME OIL PUMPS VS HIGH VOLUME OIL PUMPS – IS THERE REALLY A HP DIFFERENCE?"

If you don't see two dolphins, you need a vacation.