my understanding is that if all you do is the filter and not pipes, all the benefit you get is a reusable filter. If you do pipes, there is no circuit pn the v-rod that will adjust for the mixture. There are several opions.... dealer reflash of the ecm, a TFI or DFO, a Power Commander, or the HD race tuner. list is in increasing order of cost and tunability. There are a lot of people here knowledgeable on each of these units...
Greg
Greg