flue size to 8 inch round

[waynespizzaworld]

Building a 42" Pompeii and now planning my vent area. I recall on my last oven I think it was a 14 inch by 4 1\2" rectangular opening transitioning to the 6" in pipe on my smaller oven. Now with this bigger oven I am dealing with an 8 inch pipe and wondering what the recomended size of the lower rectangular opening should be before it transitions up to the 8 inch internal pipe? I was thinking the same size as my 36 inch oven as the door opening is the same size and just smooth it from the 14 x 4.5" rectangle to the 8 inch round.

Is this ok or is there a better choice for the size on the rectangle part of the flue at the oven entrance?

Thanks Wayne

[Les]

I've had a couple of glasses of wine and used a cheap calculator (doesn't have pi). It looks like the volume is good to go.

[waynespizzaworld]

Thanks Les

I hope those were small glasses of Wine and I hope they were delicious!

I will go with the 14"x4 1/2" transition to the 8 inch circle. Appreciate it!

Should you sober up before I head to the job site tomorrow morning and you change your mind feel free to set me straight.

[nissanneill]

I'd make the transition as large as practical Wayne, to ensure at start up that all the smoke is captured and directed up into the 8" flue.
My oven is a 40"Pompeii and has a large chimney void which works exceptionally well. Pictures are on my build posting.
However, the deeper you make it, the further you will need to reach into the oven.

Neill