Re: Simple test for oil quality on bushing engines

[Casey Lynn]

Great test if that is all you are testing. Check out "Bob the Oil Guy", his findings can be sourced to provide your answers, possibly without having to do the testing. Interesting reading for sure.
Am assuming you are not planning on changing oil ratios based on your findings. If so, you are attempting to address only one of the areas of the engine that need more lubrication.
There were a myriad of other changes that came about that allowed later, more advanced engines, to run on less oil.
Piston material (a biggie), piston pin location, piston design, ring count, ring design,ring location, ring tension, dowel pin design, dowel pin retention methods, bearing design, bearing cage coatings, crankshaft hardness, seal designs, cooling system changes, etc.
All of these changes came about and evolved in order to provide a decent service life at a reduced oil ratio. And this is just a partial list!