Hey! I got one of these great things too, and yes to your question about the charcoal carrier in the main chamber can be used as in that manner. What I normally do is flip the carrier upside down and hang it as high as I can and then take foil and cover the right/left gaps so that the heat comes from the SFB out and up and spreads along the entire length of the charcoal carrier and foil. I have noticed that I am well within 15 degrees from hot side to cool side doing this.
As far as sealing the seams, use super heavy duty foil, fold it over several times and then press it down along the edges of the lower lip, not the upper lip of the lid. Seems tedious I know, but it works well, plus it makes clean up a snap!
I have also used heavy duty foil and lined the entire bottom area of my main chamber, this allows me to use somewhat less fuel to acheive the same temp (going on the fact that the foil in the chamber reflects the heat back upwards into the upside down charcoal carrier which then spreads it out evenly to the left/right) No tuning plate needed after that.
For hitting your 225 and holding, I start my fire with charcoal in a
chimney starter, and yes I can hit 375 pretty easily using the SFB, and open upper exhaust all the way open. Once my coals are hot, I dump them into the basket in my SFB that I had made (10x7x5) and put that right next to the opening of main chamber. Shut the main door and close the SFB vent down to barely an 1/8 opening and let it burn for about 40 minutes or so.
I think I read it somewhere on thesmokering.com website someone actually did the math and found to get the optimal exhaust draw for a more complete and efficient thermal burn thus using less fuel, your exhaust needs to extend UPWARDS 2/3 the length of your main chamber. My chamber is 29 inches in length, so my chimney stack from the opening on the lid extends 19 inches roughly upward.
Also, the direction in which your SFB is facing has a lot to do with it too, is it facing into or away from the breeze/wind? The natural breeze feeds the fire and if it's not getting something, yeah, it's going to be a bit harder to keep the fire going and constant.
Placement? Where's it at? I noticed a tremendous difference this past weekend when I used my smoker in the garage (had the garage front and back door open all the way for venting of course!) I had no problem hitting and maintaining a constant 300 for over 4 hours using the SFB with an ocassional basket shake and an extra handful of charcoal at a certain point.
The biggest thing for me was forgetting that the stock therm is no where close to cooking level temp. I went out and bought a 6" high temp therm from the store, popped the lid handle off and drilled a hole large enough that I still had to wiggle a bit but was able to get the stem of the therm into the lid all the way. Put the handle back on and presto, I have a visible accurate temp gauge at grate level.
Most of my learning has come from (luckily) just firing the grill empty and learning how it burns, making changes incrementally and waiting and noting the effective changes. Get a notebook and log what you do and what you change and the outcome, you'll zero in on complete temp control alot faster because you won't have to try to remember all the stuff you did last week, just look it up and you'll already know where to begin.
I personally fire my grill 4x - 6x a week even if i'm not going to cook on it but I always try to cook something even if it's just one or two steaks. Plus it helps to "burn in" the grill faster too.
Just my $.02 worth.
