I read an SAE article a while back about this subject, but I feel like a big part of this debate should focus on flex, and not just vibration. a 4cw crank is not used in many production engines revving over 7000rpm. Flex of the crankshaft is also worth considering and the lack of a girdle makes the problem worse.
Harmonics is just a part of the puzzle, but look at all the production engines making awesome bhp/liter and the 8cw design is used almost religiously. I feel like the 8cw may have more benefits, and the real reason for the 4cw is because the accountants want to save a few bucks.
Harmonics is just a part of the puzzle, but look at all the production engines making awesome bhp/liter and the 8cw design is used almost religiously. I feel like the 8cw may have more benefits, and the real reason for the 4cw is because the accountants want to save a few bucks.