My initial and total timing are set. What I'm asking is when ported does the carb act like a computer, basically only allowing as much timing needed at on time. Since the vacuum only comes in after acceleration, does this change affect how much timing is pulled? So if you open the can wide open but put a stiffer spring in, your initial timing should curve with the amount of vacuum being applied by the position of the throttle plates. Am I saying this correctly?