I've found over 40-sometning years of doing dyno runs that the "error" part of that process can get terribly expensive. Very few engines run well with an air-cooled crankcase (big hole in the block where a connecting rod used to be!)
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!