I'm going to guess you'll find at least one rod bearing with foreign object damage from a "dirty" assembly job, or possibly a scratched crankshaft from letting a connecting rod bolt touch the journal surface during installation of the pistons. One of my former students called me a few weeks ago about a failed engine after just a few miles- - - -he had managed to install one connecting rod cap backwards while assembling the engine. He's incredibly picky about his assembly procedures, and usually does an excellent job, but this time, he got a little distracted. He does have a habit of smoking "alternative" substances, and it's possible he was not giving the engine his full attention!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!