Do I need to turn or polish my crank?
A friend of mine just gave me the rotating assembly out of a ford racing crate motor he purchased and turned into a 331. He put about 15k miles on the original assembly before pulling it out. After going over the crank most of the journals are still smooth but a few have some small scratches from wear. None of the scratches are really large enough to catch a thumbnail in but their not perfectly smooth either. How do I know when I can get away with just polishing the crank and when do I need to turn the crank? I will obviously replace the bearings, but I would like to get away with not having the crank turned if possible.