pics can be deceiving but appears your firebolt already has the rare buell factory race muffler installed......that OR a faithful reproduction thereof. that muffler along with a freer flowing air filter such as a K&N and the installation of a generic "race map" or a custom tune to your ecm will enhance both performance and rideability. you won't gain 85 rear-wheel HP as some would lead you to believe but it does improve the things that i just mentioned.
NOTE: i'd think twice about continuing to run that exhaust header wrap. disclaimer is that i not only have no experience with it....and many board members have used it without problems.......many board members have also experienced the pain and anguish of broken/cracked headers from using it. if that happens the header assembly is not only expensive but a real bitch to replace.