Two of my friends and I are building our first reverse flow smoker. I have a 200 gallon tank and have attached the link for my calculations using Feldon's BBQ Pit Builder Calculator. I understand everything except for the firebox to cook chamber opening. How do you physically measure this opening and then calculate this in order to get the specified cubic inches recommended? Any help will be greatly appreciated!
[url=http://feldoncentral.com/bbqcalculator.html?cc=0,0,200,0,0,0,46200.00,15400.00&fb=25,25,25,0,0,15625.00,15400.00,101.5&ch=6,781.25,27.65&fi=0,0,5.5,46.88,1.97&fc=12.62,17.84,125.00]Link to BBQ Pit Calculator[/url]