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Yes the motor is a pump and will only pass through what the smallest restriction allows , for peak flow . If the carb is the restriction and you increase its size that will help . My example is the heads were the restriction - they had reached max flow and a bigger carb did not help power / flow . Yes a smaller carb can restrict flow and reduce power , as I noted with the hp950 I tried plus the back to back carb test on the dyno with new heads. But remember a smaller carb will often have a better signal and can help the short times ,responsiveness , but give up a bit in the top , this can only be seen on the track not dyno . That is why I start with an 1.40/42 venturi carb for performance use , maximum power .
JMO
Tex

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... know because I kept thinking you ran a Dominator is why I was wondering how well it runs on the street. Dumb me. I guess because I would like to try a Dominator one day I just assumed you ran one. But I take it you like the carb alot that you are running now ? Ron

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I bought the carb used from a MOPARTS member several years ago. Someone had gone in and did some "funky" things to it and it wouldn't run for crap. I contacted Quick Fuel and got the OE specs on the carb and put it all back to "like new" condition. Then tuned on it to where it is now. To this point in time it has been the best carb I have ever owned. The AN boosters give a great signal that gives instantaneous throttle response.
I'm considering, or looking to change, the carb to a smaller one, or do something else to the tuneup, for the NTR race this summer. (Because I don't have a roll bar) I have to slow the car down to 11.50. I'm wanting to do something simple like putting a smaller carb on. We'll see where it leads?

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I'd consider pulling timing out of it to get to where you need to be. Much simpler and less expensive way to achieve a specific performance benchmark / E.T. than investing in and learning the tuning curve of a new carb.

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I hear ya, and will probably end up doing that, but I don't have to buy a new carb. I already have the smaller carb. I was using it before buying the Quick Fuel. With my set up, changing carbs take about 5 minutes. All hook-ups are the same on both carbs.

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I'd consider pulling timing out of it to get to where you need to be. Much simpler and less expensive way to achieve a specific performance benchmark / E.T. than investing in and learning the tuning curve of a new carb.

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I hear ya, and will probably end up doing that, but I don't have to buy a new carb. I already have the smaller carb. I was using it before buying the Quick Fuel. With my set up, changing carbs take about 5 minutes. All hook-ups are the same on both carbs.

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Thats great as when you put the smaller carb back on then I can borrow your big carb. Just joking but one day I want to try a 1050 carb. Ron

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There is no "determined size".
The real question is "how much pressure differential do you want at WOT?"
Big carb = weak signal = difficult to tune, big power: 1" WOT vacuum.
Economy car = small carb = excellent response + good mileage: 3" WOT vacuum.
Very complex carbs such as Weber DCOE, Dell'Orto DHLA have good response and signal as low as .5".

Carb CFM is not a fixed number. A 750 only flows 750 is the engine demand produces the Holley test vacuum figure of 1.5 inches of mercury. If the engine produces more vacuum (2" etc.) carb flow increases, and vice versa.

Why does high WOT vacuum reduce power?
#1. pumping loss
#2. the VE is affected by the vacuum reading. No N/A engine has 0 vacuum, which means the maximum VE (absent wave/sonic tuning) is below 100%. Theoretical calculation is
((ATM - WOT loss) ÷ ATM)^.5

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