Ok, talked directly to Kicker audio today. The 368 watt amp upgrade requires a powered sub to work. In addition, the cross over is raised for the door speakers. They never intended for someone to go directly from 322 watt (or 276w) to 368w without adding either the 77kick04 (SRT powered sub) or the 77kick20 (dbl 10" with 400w amp). He also suggested the true system potential would not be realized unless the 77kick11 (front and door) and 77kick06 (rears) are also added. His recommendation is to add at a minimum the 77kick04. He said the system difference will shock me.