I had a 379ci destroked 400 and ran it for about 3 years until it finally blew up from too tight mains. I have a 422 now using a stock block with Eagle Billet Splayed Caps shift has ranged from 6500-7000 so far without any issue's. The biggest issue I have read and heard is weak cylinder walls. I added just a small amount of hard blok to mine to the bottom of the freeze plugs maybe a little lower. It never gets over 190 even on 90+ degree race days. I think going with a short stroke helps it live too.