Back your EPA down until you see a change in RPM's then go back up slowly until the RPM's max out. Just remember the higher you can get your end points the better your throttle reponse will be.
I try to get at least 100 on both sides of the EPA.

I have also found that most engines RPM's max out before the barrel or the butterfly in the carb becomes 100% open. It is very close to 100% but not always at 100%.