Runs better with vac advance unhooked (Help)

[73 C10]

No pop. More like bub bub ba bub bub bub. Sticky valve? Flakey coil?

 

[350runner]

Check your plugs it'll open the" possibilities" up a lil more

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[73 C10]

The plugs are so new. They look brand new. I pulled wires one by one while listening and that was inconclusive. I listened with a hose since I have duals and it sounded like there was a slight ting in the passenger side bank. Paper over the pipes showed no pull. Header temps were:
Comp-Temp-#-#-Temp-Comp
142-200-8-7-184-145
142-225-6-5-206-148
142-200-4-3-206-142
152-190-2-1-187-150
Just to note the difference if there was any.

 

[350runner]

Try backing out the passenger a/f screw a lil bit to see off that helps with the ting. How did you go about setting the a/f screws?

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[73 C10]

Idle rpm, screw right in till dies off incrementally. It'll whistle a bit. Then out till dies off then set to the middle. Same with the left. Back to the right. Left. Done.

 

[350runner]

Try this way w with a vac gauge( $12 bucks at harbor freight) engine off. screw them both in all the way till they seat(no cranking on them) then back out 2-1/2 turns. Start the engine and back both out till you get the highest vac reading. That's the way to nail it every time evenly

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[73 C10]

Cool. I'll do it. I started 2-1/2 turns out after the rebuild of the carb. And every timing change thereafter. I've got a vac gauge. Vac numbers and response look good to me. 17 inches if I remember right.

 

[350runner]

Cool deal that vac reading can be that high even if the screws aren't evenly placed. You may even be able to pull it up to 20hg or better

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[73 C10]

Vac reads upper 18-19 with, standing in front, left 2-1/4, right 1-3/4.

 

[350runner]

Getting closer. Key is to back them both out evenly far as possible to achieve the highest vac reading (basically they will meter evenly)

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[350runner]

Here's a read good read on there exact functions http://www.enginebuildermag.com/2008/07/carburetor-tuning-the-airfuel-equation/

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[73 C10]

Best vac and equal turns out? Could turns out vary due to slight circuit difference?

 

[350runner]

Nope always keep em even

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[350runner]

What slight circuit diff might there be?

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[73 C10]

Worn needle? I know I'll look. Crud?