Theoretically no. In practice I have run smaller BP gaps before but on an adjustable design where I could change it. If you are going with a fixed gap then stay with the same opening or as close as practical to the size of your throat.
And on the eighth day God created barbecue …. because he DOES love us and he wants us to be happy.
Current smokers: Egor (trailered RF) and Easybake (tabletop pellet drive)
Thanks, the only reason im asking is I have been looking at some of the fuel oil tank builds and it seems like there firebox to cook chamber are bigger then they should