20" offset from scratch

[Finatic]

Have a question, I am using a 4" exhaust stack and am thinking of using an old design that I had laying around. At one time I built a internal damper, never used it and now am asking if the flapper would affect the flow? The flapper is 3/16" plate opens fully. I myself don't think it will have to much of an affect but figured I'd ask you all.
Thanks

I built an internal damper on my offset and ended up cutting it out. On my pit it did change how the pit cooked when I adjusted the internal damper. I ended up installing a heat deflector plate and controlling the temps using my intake exhaust on the firebox and that works a lot better.

[Jamie]

K.A.M. My CC is 20" O.D. (19.250" I.D.) X 36" long and the FB is 20" (19.250") x 18" long. Stack is 4" X 22.5" long.
I know how that is, I've been zooming in on all kinds of cooker internals...LOL, but once you mentioned it then I started questioning myself on how to read the calculations. Hey, any information is good information!!!!
I built the internal damper flap and never used it....most likely wont this time either, it would look cool, but working good and looking cool are 2 very separate things. Thanks all for the replies.

[k.a.m.]

K.A.M. My CC is 20" O.D. (19.250" I.D.) X 36" long and the FB is 20" (19.250") x 18" long. Stack is 4" X 22.5" long.
I know how that is, I've been zooming in on all kinds of cooker internals...LOL, but once you mentioned it then I started questioning myself on how to read the calculations. Hey, any information is good information!!!!
I built the internal damper flap and never used it....most likely wont this time either, it would look cool, but working good and looking cool are 2 very separate things. Thanks all for the replies.

You're golden brother I was just checking.

[Jamie]

Decided to not grind any welds on this build and bring out the identification stamp, that I used on code piping. Maybe the kids and grand kids will get a kick out it.