They are totally adjustable and a really nice unit. I have it set up now for 20 initial and 16 in the dist. The cam is a 254/.520 and it just seems the idle has always "wondered". I have the option with that unit to lock it out but just thinking if there is a light spring that works that someone has already experimented with I would ask the question. My next move is to try locking it out and work back form there.