Quote:
Originally Posted by alexiskai
This reminds me of a quote from another article about the same time:
“G. A. ROUND — Why is it that, in spite of the fact that the oil is applied on the wrong side of many crankshaft bearings, the units still run and have run for thousands of miles without giving any particular bear-ing-trouble?
MR. BARNARD — That is just an illustration of the enormous carrying-capacity of a thin film of oil.”
I think it’s hard to get a definitive answer on this issue because multiple oil groove designs can work in an engine for a long time. And when it does wear down there will always be alternative explanations for why it did: insufficient filtration, crank flexing, etc. None of these designs are overwhelmingly superior to the others.
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Exactly Colin. No one is going to agree to what the longevity expectation of a cast bearing in a Model-A is supposed to be either. Many tend to argue why an insert bearing in a Model-A engine is superior because they last longer than what cast bearings do. When I ask how long they expect an insert bearing conversion to last, the conversations almost always turn into stories much akin to how big of a Fish was caught. "Well ole so-and-so only got 5,000 miles out of Babbit bearings but he got 20,000 miles out of inserts!". Hmmmm, so he only got 20k out of inserts but several Model-A owners I know have over 30K miles on their Babbitt bearings and there still going strong.
Well yeah, but they probably don't have a high-compression head on theirs! You see, my friend wanted to drive his Model-A and it be reliable, so he switched to insert bearings so he could 'Tour' with his. Ohh, ok, I see!!!
In my line of work, I suppose I have about heard it all!!
FWIW, -I even remember back in the 60's as a kid when several of the club members wanted a 'B' engine in their Model-A so they could drive faster and go longer. Dad's '31 Roadster and Bill Coleman's 30 Coupe (-both with Model-A engines) showed taillights to many of those A's w/ Model-B engines when we were on our way home after a tour. I can't speak for Bill's engine but Dad's engine was a 0.125 overbore A with a milled Police head, and a NOS Model B Camshaft. Dad never told them anything other than it was a Model-A engine. So, ...when we are being transparent, nothing has really changed in those 65+ years with Model-A owners!!