that is alot of pipe and you do need back pressure ... drag pipes...work good at higher RPMS but HDs

are not high RPM bikes!! so that sweet little power band you get with all that free flow is not always the best..good luck though. CD will help ya alot!!!! IMHO I am just not a fan of drag pipes all the noise is kinda cool but when you gotta shift as as much as some of my buddies do compared to my setup I am happy with what I have. FInd out what goes on in the engine. Just IMHO...but TO EACH THIER OWN!!
ENJOY!!!!