Joe is absolutely right about a block with pistons in it trapping water. I just rescued two MOPAR 383 bare blocks that have been sitting out in the open, exposed to the weather for 15+ years. They both have surface rust on the cylinder walls, but no serious pitting. Both engines are going to get built up with 460+ cubic inches with .060" oversize pistons and 440 crankshafts, stroked an extra 1/4".
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!