have installed a dyno jet kit, white bros. e series slip on muffler, and a um products open airbox with uni filter, if i install a performance header pipe will i notice even more power, thank you, this is on my raptor

 

Pete at Powroll told me not to bother with a head pipe unless I went into the engine.
he was right. one son got the yosh full kit and i have a fmf slipon. we dragged several times and always a dead heat. no noticeable difference, just like Pete said.