Sorry, need more info
Lump, 12 lit KBB Briqs on top. I can get it to 275 but it settles at 250. Water pan with foil on the inside and a pizza stone laid inside. I can keep this temp fairly well, It seems everyone else can keep this 250ish with most of their vents closed. My last couple of smokes have been on calm days. I am using a Maverick ET-372 with my probe in the center of the top rack. My ultimate goal is to extend my cooks. I have worked with the fire door to shape it better.
WSM 22.5", Little Chief, Weber Spirit 300