+1 on the variations between cylinders! I had a pull truck MOPAR 440 on the dyno one night, pulling 700+ HP at 6500 RPM on one 4 barrel and gasoline (Super Stock class rules didn't allow multiple carbs or alcohol) when one intake runner developed a tiny air leak. In less than 10 seconds that piston had a half dollar sized hole in it!

The Holley 4 barrel that GM put on one of the road-racing 427 Corvettes had four different-sized main jets to account for intake runner variables!
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!