Well, 72 was produced by a motor with Wiseco pistons, VHM heads, ported barrels, ported an flowed crank cases, rebulit crank, PWK 39 carbs, HRC air box etc etc and built by the best.

You can take it from there.

Of course you could get 80hp if you got a crank figure of some degree.
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If I have to take the carbs off once more...