It seems that new crankshafts are being ground right at the high limit more and more these last couple years. The extra clearance bearings are the easiest solution if you can get them. We had a 440 crankshaft in class we just couldn't get extra clearance bearings for. It had .0008"-.0012" clearance on the mains. We had to send the crankshaft to Shaftech in Fostoria, OH to have it ground .0015". It came back very nice. But a 6 week wait and not very many shops can remove such a small amount of material properly. You really have to know what your doing to make that happen. The average crankshaft grinder and operator would probably turn the crank into scrap.
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