Which type of oil to use

Newbomb Turk said
Or, his clearances are correct.

This is why brother Newbomb is constantly harping on guys to tighten up their clearances to 21st century standards.

My climate is sub zero to 100F plus. I used 5w30 and it was a bit on the thick side. This time I'm using 0w20.

Even off the shelf oils are so much better today that there is no real reason to run a 50 grade oil.

And why these companies still produce single grade oils baffles me.

You can see the OP gauge under the hood when the pump dumps the relief valve open. It hits 75 PSI idling cold and will NOT budge another millimeter when you goose it. She idles at about 50 or so hot, but AS SOON AS you give any throttle at all, it zings right up against the relief valve at 75. Melling says the HP relief spring is 70 PSI, but it gets a little more before it dumps open.