| Hi J-rod007,
That convection plate works really well. As you can see the holes get larger the further away from the coal box it gets, that blocks the hottest air, nearest the opening and allows it to rise further away, theoretically helping to even out the temperatures. I don't know how it happened but when I bought my Brinkmann Longhorn it came included with it (I'm not complaining mind you). The only downside to this (not a big deal) is that the holes will get sludged up a little and are a pain to get completely clean....if I had a pressure washer then this would not be an issue at all.
If you notice (near the top of the photo) there is a weld line where an additional section was welded to fit the 20" diameter of my cooker. It looks like the original sized plate was made to fit the 16" diameter cookers and Brinkmann added the extra piece to fit the 20".
You are definitely going to need some type of baffle/plate to force the heat and smoke further into the chamber. If you know someone who does welding, they appear to be easily made...the thickness of the convection plate is between 3/16 and 1/4 inch, so its nice and heavy. I could measure it and get you the dimensions, if ya want to try and have one made, just let me know.
Best regards, Mark D.
Remember, two wrongs don't make a right...but, three rights do make a left
Charbroil Silver smoker
Weber One-Touch Gold Kettle grill
Member since 6/26/2005