Is a 4x8" flue liner too small for a 42" dia oven?

[vincentvintris]

Hello,
I just got a 4x8" flue liner and looking at it makes me think it might not provide enough draw for the relatively large Pompeji oven.

is this really big enough?
How tall should the chimney be? Does it matter?

I was planning to notch the two vent arches and set the flue liner on top of the arches. (only the first vent arch is shown in the picture. Another one planned about 4" in front of the shown arch)

Thanks
VV

[Dutchoven]

Re: Is a 4x8" flue liner too small for a 42" dia oven?

Well the recommended sizes for the ovens in the FB family are 6" diameter for the smaller and 8" for the larger ovens. And as I remember the oven plans recommend 6" by 10" opening for brick or clay flues. I would say go with something bigger so you don't have to worry about smoke in the face.
Best
Dutch
Oh, by the way nice work on the oven so far.