Andrew Gideon wrote:




So the rough running is called by cylinders generating different power
levels? Why can't that occur anywhere in the air/fuel mixture curve?

Assuming the moving metal parts are very close together in weights the
only other thing that will affect noticeable vibration is the cylinders
making different amounts of power. If you can get each cylinder to peak
within about .2 gph you will have a very smooth engine indeed.