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Discussion Starter · #1 ·
Where would be a good place to get the best vacuum signal for my gauge? I "wanted" to use the port on the back of my intake but the fuel inlet lines block access to it. The only way to get to it is if I use a carb. spacer but I don't want to do that right now.
Could I use the small vacuum port on the front of my holley as a reliable source?
I want to get a vacuum reading during full throttle to see if I have the best power valve or not. Right now it's a 6.5
 

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Hi there.

You want to use the Vacuum port under the front of the carb. Not the Timed port next to the fuel bowl viewport.

I run with a perminate vacuum gage in my dash board.

Anytime you are at WOT, you will be between 0 and 1 HG, through all the gears, till you start to let up on the pedel, then it will increase dramaticly.

There is alomost no reason to run other then a 6.5 valve for your engine setup, unless you have a really low 6 - 8 HG at idle. If so, then drop to 4.5 or lower. MAKE Sure you check this in gear. You will have a lot higher HG in nutural and that reading means nothing. With your set up, you should be making at least 10 HG in gear, or your carb or timing is not adjusted correctly.

You do not want the valve to open for small changes in throttle position, you will waste lots of gas. You only want it to open when you want to make real power, othrwise you will fowl up your plugs real fast.

Running with a full time vacuum gage, you will quickly learn all the secrets about carb and timing that are just guesses otherwise.
 

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Discussion Starter · #4 ·
Thanks guys
 
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