Because I did not HAVE to have the crank journals ground...they polished up very nicely...I wanted to make sure that there would be no constrictions to good oil flow through the block.

The main bearing journals in the block were align honed to make sure that the crank would lay in perfectly true.

With the low mileage on the motor, The main and rod journals on the crank did not require grinding to undersize. Polishing the journals would suffice. They were polished.

With the crank journals polished, and using STD size mains and rod bearings, my clearances were going to be just the slightest bit larger that I prefer. Instead of being right at 0.0015in [mains and rods], the polished crank journals would increase the clearances by a couple of tenths of a thou [0.0002in to 0.0003in].

Those extra couple of tenths would not be a problem. BUT, I wanted to make very sure of that. And one way to make SURE of that is make sure that the oil flow GETS TO WHERE IT NEEDS TO, as easily as possible.

This picture shows two of the three places in the block oil passage system where the variations of the machining procedures at the junctions of oil passages create places of constriction and unneeded turbulence.