That's horse feathers. There won't be 100 HP worth of strength between a "good" number block and a "bad" number block. There's no real evidence to support it either way, really. Just a bunch of bench racin BS. I know somebody that runs a stock stroke 400 in a 10 sec gasser Gremlin and a 451 in a strip only 10 sec Dart. Neither of them is the purported "good" block and they've both been together for over 5 seasons. "Only" as good as the 383 or 440? Oh gawd, I guess now we gotta throw all those away. ....rolls eyes......