If you already have an FMF mufler, I'd think your EXUP valve is no longer on the bike.
If so, might as well get rid of the electric servo motor that used to control the EXUP valve.
I'd get rid of the airbox flapper, get rid of the AIS (Air Injection System), and gear the bike considerably lower if you want acelleration.
Details are on this message board in the Sweet Mods forum.