This would unfortunately be a time paradox, as Mike Tyson would have been about seven when Bruce Lee died. An all-out showdown between them in their prime would definitely go hard as hell though, though it would require a bit of time travel.
Probably not though. Bruce Lee knew his limits and going up against a heavy weight boxer twice his size was something he knew was a bad idea. Something about his fist being "a Chinese fist". I believe I also read that Chuck Norris praised him as being "lbs. for lbs. the strongest man in the world." But that's an allusion to how incredibly fit he was.
