The Stovebolt Site Forums The Shop Area Engine Shop 50w motor oil?

Everyone needs to remember that the low pressure engines use drip oiling on the timing gears and that's a mighty small line running to the rockers for cold 50 weight to push through. While thick oil has it's place I wouldn't run it in my '38. Many folks say 10w-30 is fine and while I admit to having used it in the past in my '38 I prefer 15W-40. I once read a technical paper that claimed multi-viscosity oil's viscosity modifiers morf into a single viscosity over a few heat/cool cycles. I don't remember the exact figures but a 10-30 would end up equivalent to about a straight 20 weight over time. Was the author full of beans? Beats me but it's something to think about when mulling over what oil to use.