Another option which I'm setting up to do on all the stovebolt engines I intend to build going forward is to machine all the main bearing journals to the same diameter (Chevy small block 400) and put reducer bushings in the block to equalize the bore sizes. That eliminates the 4-size bore problem. Then I'll line bore and line hone the block one time and have newer, more affordable main bearings to install. I'll also machine the thrust faces on the #3 main web to use a permanently installed bronze thrust washer instead of a flanged bearing shell to control crankshaft thrust.
Jerry
I haven't gotten to measure anything yet. Why will you need reducer bushings? Does it really have to be opened up so much that there aren't over sized bearings that'll accomodate it?
