it might run at 16 if your reclaibrated the carb and idle speeds.
See your playing with a finely tuned and calibrated set of circuits. Affecting one affect's them all. Getting them all correct means a lot of trial and error with a degree of systematic logic problem solving. You cannot change just one thing and always expect better result's.
IT'S ALL IN THE COMBINATION!!!!!. is never more true
You have to verify timing marks are correct. Otherwise, your chasing your tail and your gonna catch up it eventually. OUCH!!