Big fire box question

[CarRAMrod06292011]

Do you really need a fire box a third the size of the cooking chamber? I have built a 30 x 30 x 30 inch double wall firebox for my current trailer smoker. I plan on building a bigger 36 x 50 x 111 inch cooking chamber with double wall 10ga and 2 inches of insulation. This will be a horizontal smoker with tuning plates along with 4 48x48 inch pull out shelves. I use 24 inch split logs in it currently. Is there some point you do not need to follow the normal rule of the fire box being a third the size of the cooking chamber? I mean 6 18-24 inch x 8+ inch diameter logs is a really big fire. Any help from someone who has experience with building big smokers would be greatly appreciated.

 

[kmmamm]

The objective is to balance flow air through the system. Not simply fuel (split/log) capacity. If the fire box is too small, the cooker will not be able to draft (breath) correctly. Improper draft can lead to highly undesirable things like erratic cc temperatures, sooting, creosote build-up, etc.