2 vents on weber lid for uds

I have thought about this in the past as this would possible even out the air flow a bit so it wasn't just drawing towards the one vent. However, I have never had an issue with just using the single vent so I figured I would not risk jacking up the lid to install a second.

some have done that to their wsm's and were happy with the results. don't see any negatives to doing it. let us know.

Pappy said:

You could always do half & half.

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mbshop said:

some have done that to their wsm's and were happy with the results. don't see any negatives to doing it. let us know.

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Yeah, if you are confident in your skills to pull it off without ruining the lid then go for it. One my main UDS I have already flattened and bent the lip around the drum and did not want to jack with that again in case I didn't drill the holes correctly and the lid had issues.

I'm adding a second set of vents on my dome lid for doing chicken.
I'm not sure which way to go yet. I've seen it done a couple of different ways, either a bung hole or 4 smaller holes.

I think the general rule of thumb is twice as many exhaust holes as intake. So if you have 3 1inch intakes you should have 6 exhaust holes. With the weber lid vent and cover, if you wanted to duplicate that you could drill the same hole config then cut a piece of sheet magnet to mimic the original vent cover.

I'll add a bit of input here.

Typically the air intakes are 3/4" ID not 1". The original drilled hole is a 1" hole meant to accept a 3/4 pipe nipple.

Norco somehow or other came up with the 3ea 3/4" holes and that size and number of holes has pretty much been accepted as standard procedure. I have the Norco style holes on mine and I can get my heat up to 325 with a 10" diffuser plate with only 2 holes wide open. With the third hole open I imagine I could go as high as 350 or more.

Anyway, Norco also claims and others agree that 8ea 1/2" holes are sufficient for the top exhaust. I haven't done the math but I'd guess the 8ea 1/2" holes are a comparable or a larger surface area than 3ea 3/4" holes.

I do know that one Weber vent has 4ea 7/8" holes. I did the math on this and I know the 4ea 7/8" holes is a larger surface area than Norco's suggested 8ea 1/2" holes.

So to sum this up, if you think more/bigger exhaust is going to improve your smoking I don't think it will. But it may create a more even heat disbursement and reduce any hot spot you may have below the one vent wheel. Part of Norco's reasoning for the 8ea 1/2" holes was to spread out the heat exhaust, lessening the potential for hot spots caused by the heat exhaust focusing towards one vent.

Hope this makes sense.

Carbon, I could be wrong but I don't think adding more exhaust will raise your heat for chicken. Raising the heat requires more O2 getting on your fire or less diffuser spreading out the heat.

Those extra vents on the dome are needed when you go full throttle on the intake. Let that drum breathe....Ahhh.....

Carbon said:

Those extra vents on the dome are needed when you go full throttle on the intake. Let that drum breathe....Ahhh.....

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I've never been above 350 degrees and only when I seasoned it. 350 was not yet full throttle either.

pman777 said:

I've never been above 350 degrees and only when I seasoned it. 350 was not yet full throttle either.

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Perhaps I don't have enough fully lit coals in the basket when I'm doing chicken, for instance. I'm having to keep the dome lid slightly ajar to stay at 350F.

Carbon said:

Perhaps I don't have enough fully lit coals in the basket when I'm doing chicken, for instance. I'm having to keep the dome lid slightly ajar to stay at 350F.

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Are you saying you have all 3 vents wide open and 350 is it?

pman777 said:

I've never been above 350 degrees and only when I seasoned it. 350 was not yet full throttle either.

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I built mine with (6) 3/4" exhaust holes in the flat lid.
(4) 3/4" pipes for air intake. 2" from the bottom (3 w/caps & 1 adjustable)

For Chicken I run all the exhaust holes open. I close off 2 holes if I'm trying to hold the temp. down to 225. I use drop in pipes with Black screw on caps for the additional adjustment/lower temp. I made a total of 6 of them so I can damp out the fire. I know it's low Tech. but it's easy and inexpensive.

yes they do.
http://help.weber.com/schematics/view.aspx?Model=71001&Sequence=2

Pappy said:

I guess I will have to make my own vent dial or get one from a used grill. Weber does not list them for sale on weber.com

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Having two vents is unnecessary. The weber product is highly engineered with fancy CAD/CAM/CAE software. If there was an advantage to it, it would have already been done.

A lot of weber stuff you just have to call them and order it directly. They sell all replacement parts, but don't list them all on their website.

NorthwestBBQ said:

Having two vents is unnecessary. The weber product is highly engineered with fancy CAD/CAM/CAE software. If there was an advantage to it, it would have already been done.

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Yes, but it wasn't engineered around a 55 gal drum.