I'm with you 100%! I assume when the factories built these motors decades ago, they probably didn't balance EACH motor. They probably balanced one motor every so often and applied the same measurements to the next 100 or so. OR they "balanced" it with huge specs so it was "good enough". I think that's one of the reasons engines were only good for 100k back in the 70's and 80's.
BUT there are plenty of shops that will say factory is good enough. "Ahve beelt hunnerds a motors without balancin'. Dats fer dem high per four mans enjuns." I say "No, its for anyone that wants their bearings to last more than 100k miles under normal use."
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