Fordboy, I appreciate your (and everyone else's) opinion. It does look like loose soft metal (aluminum?) swarf that was not completely flushed out of the block. That is completely my fault, I should have been more careful.
Regards, Neil Tucson, AZ
Neil,
x2 about Line-to-Line.
Some other, random thoughts . . . . .A/ It's your Lucky Day!
Well, because it's a Chevy. Race bearings are available in .001"
under size, so if your crank polishes up slightly under spec, you can use a set of those. And .001"
unders, are available for many engines. King lists .002"
u/s for Chevys, in both mains & rods.
2/ Don't get paranoid about getting all the cylinder "scratches" out by honing the bore. Tiny, fine scratches, (not DEEP ones), while not ideal, can be ignored. Anything that is equivalent to service wear is acceptable, UNLESS the cylinder is "out of round". O/o/r conditions prevent ring seal with "tool steel" rings. Softer rings can accept more o/o/r. And, BTW, forget about cylinder scratches in the lower 1/3, or so, of the bore. Rings don't go there. Bore should be smooth enough so that the piston skirt is not "compromised". Chromed, steel aircraft cylinders are purposely "scratched" by specialized honing methods and/or reversing the plating polarity. Those small to tiny "defects" hold oil essential for piston skirt lubrication.
d/ On most "conventional" engines, the mains are fed oil first, and then oil flows to the rods from a combination of oil pressure and rotating forces. "Nose fed" crank oiling is an exception to this convention. Crank oil passage drillings & rpm range used, determine whether a crank requires a "low" or "high" pressure for bearings to receive adequate oil. Additionally, pressure is somewhat misleading as it is the oil pressure, plus the volume of flow, plus the flow timing, that keeps the surfaces out of contact. Note that many specialist produced "Chevy" type blocks use "priority main oiling systems". These systems are designed to prioritize oil feed to the crankshaft. Mains first, then rods. Everything else, after that.
JMHO and YMMV
Fordboy