Regular tuning, tappet adjustment, good quality wires, plugs, maintain proper inflation of tires, clean the negative ground connection if rusted and if possible add additional grounding with 0awg wire.
Also do not get the carbeurettor serviced if its not giving any problem. And if you have had a carbeurettor serviced in the past most likely the fixer messed it up.
Follow the above mentioned protocol and youll not be disappointed.