I am glad you posted this question. I have a 14lb packer that I was planning on cooking this weekend. I am cooking it on a Kamado Joe, and I have a temp controller. I completely understand the "its done when its done" statement that everyone makes. Unfortunately that makes it very difficult for anyone who has never cooked one to have an idea when it might be done. You see times like 1-1.5 hours per pound thrown around as a general guideline. Well for my 14# packer that would be 14-21 hours. That is a 7 hour window of unknown. I have cooked a bunch of pork butts, and they are also never exactly the same. But I have cooked enough of them to have a general idea, that on my cooker at 250F, I can usually count on an hour a pound to get to 195-199 internal. Sometimes it is slightly longer, and sometimes slightly less. So if I am cooking a 8 pound butt I start checking around 6.5 -7 hours to see what kind of progress I am making, and can adjust from there.
So I guess my question would be does anyone have an idea how long it would take them to cook a packer brisket ( size / temp ) on their set up?