Ive got a 434sbc with a bad crank now. The thing in the back of my mind is the stock 4bolt 400 block. It is studded everywhere but I know it has it's limits. Since I need a crank would I be crazy to jump ship to a 383 and a stock 4 bolt block? I hate to buy a good block!!! Motor runs 5.80's with no problems for a few years until i spun a bearing. whats yalls opinon?