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Discussion Starter #1
Where can you find the specs for the Power Valves in a 4150 Holley Carb? I have looked in the Service and Overhaul manuals sec. 6M and the jets and everything else are shown but nothing on the power valves.
 

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Discussion Starter #3
https://documents.holley.com/techlibrary_carb_numerical_listing.pdf

Not sure what number yours is, but the column is right in the middle.
The carb is 4160 3419 66 Chevelle. I am adding a secondary metering block and setting it up as a 3245 for my 66 Nova. I tried to find what I need on the chart you posted but it made my brain hurt. With the cam I'm using I may need a different power valve. I'm going to have the carb set up by a good carb guy. I think you have to use a vacuum gauge to see if the power valve is the right one if you are running a different cam. I'm running the Comp 30/30.
 

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Is the power valve for the primary or secondary side?

For the primary side I've always put an extension tube on my vacuum gauge and divide the vacuum by 2 and use that number for my power valve. My cam doesn't make a lot of vacuum, so my carb needed a 3.5 power valve.
 

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Discussion Starter #7 (Edited)
Is the power valve for the primary or secondary side?

For the primary side I've always put an extension tube on my vacuum gauge and divide the vacuum by 2 and use that number for my power valve. My cam doesn't make a lot of vacuum, so my carb needed a 3.5 power valve.
Both. The rebuild kit has one power valve. I want to get the car started so we can do the vacuum check. I still need to get the secondary metering block refinished so I'm not in a big rush. I have the chart but I'm not sure I'm reading it right.


Looks like the choke pull off linkage rod is going to have to be fabricated. I heard no one makes it.
 

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My 355 makes about 8-9inches of vacuum , i've been told by the formula that i should be using a 4.5 power valve , i've tried a lot of different sizes and i've found the 6.5 works best for me , just saying
 
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