Advice on setting up Dual Carter AFB's....

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Brooks James

Brooks James

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Carbs are 2992's that I got from @hemi71x

I'm thinking Hemi Style Progressive linkage

My thinking is gather jet kits, needle and spring assortment, plenty of spark plugs
And an AFR gauge.

Read recently to block the idle on the second carb by soldering down into the idle circuit.

Any help appreciated !!

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I bought this dual quad D66 with vintage AFB carbs from @FWDLK Frank He is quite knowledgeable on this setup and can probably help you

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Yup. Sure looks like it. I've never heard of soldering the idle passage. That's an interesting approach. I think I might try it in such a way that it could be reversed.
 
For a couple seasons, I ran two 800 cfm AVS2 Edelbrocks on a 440. I did not use progressive linkage, I ran 1:1. The setup ran great on the street, and got the 3700lb car (with me in it) down to 11.1 in the 1/4 mile.
A couple notes:
1. Never heard of soldering the idle on one carb - I would not do that mod. You will be able to dial in your idle mix with the AFR gauge.
2. I think progressive linkage complicates things. Keep it simple........
3. Your ignition timing will be critical (like always) but in a dual quad with a bigger intake plenum area, you will need to spend time getting the timing right for the setup. It will likely want more advance, and a quicker curve.
4. Converter and rear end gears to be matched with the above.
5. Don't be intimidated by the tuning. Just make small subtle changes ONE AT A TIME.
 
Probably wouldn't hurt to have a carb sync tool.
They sit on your carb and you adjust them looking at a bubble, match the bubble on both carbs and you have the airflow really close.
That's how we did mine during dyno tuning.
 
Soldering the idle cct. I suspect he means soldering the end of the idle tube that hangs out the bottom of the primary booster. It would also be better to use the idle cct in the rear carb & block the front carb idle cct. This will give more uniform distribution.
 
Yours is a Single plane manifold with VERY short runners. This makes it difficult to get the fuel mixture balanced when you are using one carb in a progressive way. I would at least try setting them up to open simultaneously. Much easier to set up. I would recommend that you get someone with the correct equipment to balance the carbs if you do this - not difficult but you need the right tool to use. I use 2 500 Edelbrocks on my 340 and they Have to be used simultaneously since they are on a crossram and they work Great!
 
Brooks James said:
Read recently to block the idle on the second carb by soldering down into the idle circuit.
Click to expand...
Why would you do that? You want the idle of the second carb to help distribute fuel at idle to the other 4 cylinders.

That makes no sense at all.
 
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