I'm very interested in how air flows from the charcoal chute into the cook chamber.
I was closely looking at an Old Country Gravity Feed. But I kept reading about it taking a long time to get up to temp. It seems there were air flow problems. An ATC was a small improvement for some.
But I looked closer at how OC designed the cooker. They forced the air down with a baffle inside the cook chamber, as I've marked in the pic below. And then it flows under a deflector plate. I think hot air is never meant to flow down and my theory is that and the two 90* turns, creates the air flow problem.
From what I can tell just from user pics, other GF makers have air flowing directly into the bottom of the cook chamber and then use a deflector plate. Its a straight shot into the cook chamber from the charcoal chute. The actual fire box is below the bottom of the cook chamber.
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