2kMarauder, It is best to at least install a stage one jet kit when running a more free flowing exhaust than stock on these bikes and if any modifications to the air intake such as K&N filters or modifying the stock air filters, a stage two kit is recommend. These are lean running bikes by nature and changing the pipes or air box causes them to be too lean. I have an '03 Marauder w/stage one kit and Hard Krome 2-3/4" Big Straights on mine. Not to take anything away from this fine site, but take a look at this site for Marauders and Intruders
http://forums.delphiforums.com/mig/start/ to find out pretty much all you want to know about Marauders.