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Hesitation off idle

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Old May 24, 2021 | 09:41 AM
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Default Hesitation off idle

Hi All, I finally have everything put back together. Set timing and made sure the following actions were covered: Issue is hesitation off idle
  1. Verified #1 was TDC on compression stroke with rotor pointing directly to plug one on distributer - mechanical verification cylinder 1 was @ TDC
  2. I cleaned the original Q-jet and verified it has fuel streams upon pressing the throttle off idle
  3. Checked all vacuum lines including the shift module for leaks - all new vac lines
  4. Once I get off idle while driving it bogs then goes and shifts ok
I did replace all the intake manifold gaskets and torqued bolts to spec, new carb to manifold gasket, new plugs, wires, distributer - missing something I suspect, thanks Jeff
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Old May 24, 2021 | 10:18 AM
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What is your timing set at?

Jebby
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Old May 24, 2021 | 10:38 AM
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RIght now it is set for 12 degrees BTDC I tried 8 and 10 and the stumble was worse including a few small backfires
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Old May 24, 2021 | 10:45 AM
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You need to set it at 36 degrees revved up at or around 3000 rpm......do not worry about the initial advance at idle. Also....make sure your vacuum advance is connected to full manifold vacuum and that you are setting timing with the vacuum advance unhooked.
Contact Lars for his timing paper....it is explained in much better detail.
V8fastcars@msn.com

Jebby
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Old May 24, 2021 | 10:49 AM
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Thanks!! My VA is attached to the drivers side vac port on front side of car - this was the original location prior to taking everything apart. I have Lars papers and will go back and re-read them, Jeff
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Old May 24, 2021 | 10:53 AM
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I believe that is ported vacuum......verify by seeing if it has vacuum at idle.....that is what you want.

Jebby
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