I do know of one engine, a 400 Pontiac in a Formula Firebird a buddy of mine split the rear main cap in half while torquing the oil pump bolt. The engine was in the short block stage, bored, tanked etc & pistons/crank already in. He took a chance & replaced the rear main cap w/a used one. He had no desire to tear down & no money left for line boring. The last time I saw him a few months back, the car still ran fine & has never knocked or had any issues, has been 15 yrs & 80k miles or so. I am still amazed.
