Quadrajet Problem Solving > Dialing in your rebuilt Quadrajet carburetor

Freshly rebuilt carb running ruff

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cj7:
Alright, finally opened up my carb again and got some measurements
 and bumped up fuel PSI to 5.

idle tubes are .042
idle down channels are huge at .054
Upper and lower  idle air bleeds at .063
mixture holes are at .055
there are also idle bypass holes at in the base plate

I'm not exactly sure what to enlarge or by how much, so I could use some help with that. one thing I am confused on is in addition to the 2 pairs of idle air bleeds in the body, I have a pair of larger holes in the air horn right next to the scews located inside the chamber. the holes seem to share the same channel as the upper idle air bleeds, so I'm slightly concerned I have mix-matched parts. I will attach a pic.

I also have been tinkering with the APT, and it cruises a lot better, but still leans out under light throttle and going uphill a bit.

cj7:
After reading more of cliffs book, I think the large holes are just very large MAB, correct me if I'm wrong.

cj7:
Lower idle air bleed is actually closer to .059

Kenth:
Here is the original recipe:

      454 Calif.
Carb #      17058512
Main jets      71   
prim.rods      35L
idle channels       .054
idle tubes      .041
upper idle air      .069
lower idle air      .063
idle air bypass      .049
idle discharge      .054
main air horn      .120
main air body      .066
main air nozzle      .029
sec rods / hanger      DR   /   K
sec acc. / pri acc      .035 / .025
sec air tube / Fill      .025 / .039
idle screw   taper   L 3,5 /
sec air valve/APT      31mm     / 4,0

For a 350 i would use .038" idle tubes, use .050" main air bleed inserts in air horn and float bowl with the original jetting, if you only have #76 jets and about #46-#48 primary rods i would open the float bowl main air bleeds to .120".
Open the idle air bypass to .080" with choke channel closed off.
Also, i would open the sec. acc. POE to .052" and use DA secondary rods.

cj7:
Would there be any benefit e.g. fuel economy, from going to the smaller inserts and jets? my MABs are already .120. I do like the idea of opening up the idle bypass, but is that for both pairs or just the upper idle air bleed pair?. Also, I'm not entirely sure what you mean by "with choke channel closed off."

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