Originally Posted by 75GMCman
How are you guys making these cranks break ? (racing, dyno, race engines)?
Just starting it up! I had a customer use one sometime back in a 400. Where they drilled thru the front rod journal with the big 7/8" or 1" hole, they got the hole off center and too close to the underside of the journal. And just cranking the engine to break it in, it collapsed the rod journal and lost oil pressure. Upon teardown, it was found that was the cause, and measuring the thickness, it was only about .070 thick on the top side of the journal.