Castrol GTX 20-50

Do you drive any of them in winter? It’s definitely a decent oil, and it’s got zinc. Cold starts in under 50* weather would be my only concern. Not catastrophic, I would just make sure to bring it up to temp before any spirited driving. Oil pressure gauge would tell you when you are good to go. I run 20/50 in my bikes and my Mopar’s, but they don’t see any cold weather.

I am convinced you can put anything from corn oil to bag balm in the slants crank case and it will run just fine.