I guess it seems to depend on the bike. I actually had the FP3 on, before I changed the pipes and it ran great. I just wanted a little more sound and a little less heat so, I threw on a set of decatted headers. All I got was erratic idle speed, hesitation and all other kinds of crap I wasn't expecting. I went with the base map recommended by V&H rep ( High output w/Power Duals, standard baffles, was told not to auto tune, due to the cross talking O2 sensors. I've tried other base maps, auto tune,no auto tune, Knightrider VIED's to try to richen the mixture. Took them off, went with Fullsac, runs the nuts, no more problems.