First, be sure it’s a whole brisket, not just the flat. Time will vary, but roughly 1.5 hours per pound seems to be my go to. Briskets are one of the harder cuts of meat to cook properly, don’t be discouraged if you mess up your first couple, it takes time to perfect. I’d suggesting researching different techniques and recipes (Aaron Franklin is the Yoda of brisket making, read and learn). Rubs, how to trim, whether to finish in foil or not can vary. Also, use hickory and mesquite wood, a little secret, pecan is amazing too if you can get it. Remember, time is your friend, slow and low that is the tempo! Here is a pic of my last one! Send pics of yours’ (brisket of course).