Vacuum Advance to Carb Location

Joined
Feb 28, 2022
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49
Location
Austin, TX
I'd appreciate thoughts on where I should look to connect a vacuum line from the distributer to ???

The other question I have is the best/ideal setting for the fast idle. Is there a baseline I should start from and work from that point? For example, screw until it touches the plate and then back off 2 turns or something like that?

1973 F 155. I think it's the OEM carb but not 100% sure. I recently got a vacuum adv distributor from sor.com to replace an old remy deco. Should I be attaching the vacuum advance outlet (circled in red on the right) to a vacuum port directly on the carb? There is no VSC. The pic on the left shows the only ports I could find on the carb. I was hoping I'd see one next to the idle mixture screw on the other side but there is no port. I'm clearly new to this, but enjoying the learning process so any thoughts are appreciated. FWIW the truck does drive pretty well right now. There is more hesitation than I want when I need more power in the 40-45 range and I'm playing whack a mole with carb adjustments and trying to better seal the exhaust.

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liven the life

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Dec 7, 2018
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Omaha, NE
Not sure about the fast idle tips & tricks but the vacuum port for my dizzy goes straight into the base by the idle adjustment screw. Note the small black vacuum line going in to the base of the carb.

PXL_20220626_002513656.jpg
 
Joined
Feb 28, 2022
Messages
49
Location
Austin, TX
Awesome. I see it now. Thanks for the pics. I see now those plugged holes off the carb. My pic is below. I guess I just pick one and run the hose to it. Thanks!

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fjc-man

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Wrong, the pictured vacuum line is attached to a pipe just to the right of that mix screw. I think that can be drilled in that boss on the carb that doesn’t have a pipe, but haven’t done that myself. Anybody want to chime in on how to accomplish that?
 
Joined
Feb 28, 2022
Messages
49
Location
Austin, TX
Wrong, the pictured vacuum line is attached to a pipe just to the right of that mix screw. I think that can be drilled in that boss on the carb that doesn’t have a pipe, but haven’t done that myself. Anybody want to chime in on how to accomplish that?
got it - upon further inspection I think he has the pipe going into the base of the carb where I have circled in green. I initially thought I could pop out one of those silver caps (?) circled in red but maybe not.

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Joined
Jul 5, 2005
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Ames, IA
If your distributor is vacuum advance:

i-3W7WtTZ-M.jpg


If you can't find a carb with the proper ported vacuum port, it can be drilled out and added by a pro. I sent one to Jim C and he drilled it and added the tube for a reasonable amount with quick turn around. @FJ40Jim
 
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