OK here is the engineer answer....
If the intent was for an efficient smoker, an insulated vertical smoker would be the ticket! Since heat likes to go up they are very efficient at using the heat. However, because they are so efficient they don’t need larger fires and depending on the design they need a “heat tamer” i.e. a pan of water or deflector plate to calm the intensity of the heat down to the low temp desired. This is also why they are pretty much a coal-based smoker.
A reverse flow smoker by design is not very efficient because it directs the heat/smoke in ways it doesn’t want to go. However, what this does is create a radiant convection oven that when properly design/constructed provides for very consistent low to mid-range cooking with coals and a wood fire.
Now to the X-Fire Grill design. The fire bricks are there for heat control. They act as a heat tamer because they absorb the heat and thereby tame the fire. Once hot, they radiate the heat back and at this point they help regulate the heat and can even increase the intensity because they are adding back the radiated heat. Now Weedeater is exactly right that the bricks will take considerable time to heat up, i.e. most brick smokers take an hour plus to get up to a consistent smoking temp but once hot they release the retained heat and help stable the oven temp. This is also why most brick smokers are vertical and not horizontal because they need the design efficiency to operate efficiently. Most individuals don’t want to wait 2 hours plus for their smoker to heat up.
So, the design theory of this build is to use the absorption quality of the brick to allow for a wood fire to be used for heat and smoke. Again, smoking is a secondary function of the grill, but I believe it will function very well at convection and indirect heat/smoke cooking when the doors are closed, and a small fire is burning. I also believe I will be able to reach higher temps (roasting temps) in the range of 375 to 425 and maybe even higher with a big fire. I currently have 4 smokers (each with their own function), so I wanted to try something unique. Worse case I will have a nice Argentine grill and I’m perfectly OK with that (Commercial ones that are brick lined go for 7K to 10K or higher). So, if I can roast a chicken or turkey or fast roast some ribs in addition to the grilling I will be ecstatic! I might get kicked off the forum for saying this but not all cooking has to be done low and slow....
