Selection of the Right Motor Oil for Flat Tappet Engines

[richardlw]

Since this applies to more than one model, I'll add it here too. It's not a sales pitch, just a contribution I hope is useful.
Someone posted this somewhere around page 43 of another thread and I see people jumping to the end to ask questions that were answered. I thought it would be good to be where people will see it up front and get a good overview of what oil does and how to decide what to use instead of the opinions of others who may not know the facts.
It was originally written for the Corvair, but 95% is applicable to the rest of the flat tappet engines (and others).
It grew from the original project, but most have written that it is worth reading all the way through.
Hope it helps.
Selection of the Right Motor oil for the Corvair