I have an '04 mean streak and one advantage over most. I am employed at Superbike Specialties. I deal with after market parts all day. I have a similar set up on mine. I have a Hypercharger with HardChrome 3 inch straights and a PC III. Mine was breathing fire in the begining. Make certain that you have the proper map loaded in the power comander. Once you are sure that you do all should be well with the misfiring issue. If you start to get a backfiring issue on decleration turn the zero throttle position up 4 or 5 and it helps with that. Have fun.