[srmmmm]

Finally had a chance to take in some of Cliff's experienced recommendations and did a careful reassembly of the carb. Three discoveries along the way: 1) wrong base gasket (left side of picture), 2) float height was set at 5/8" instead of 5/16", and 3) float pivot pin protruded above the level of the float bowl casting lifting the float bowl gasket and potentially binding the main metering rods.

It's back on the engine but waiting for daylight hours so I don't wake the neighbors when I start it.

[Kenth]

The previous history of this carb mean NOTHING. Obviously your carb is a hack-job from Quadrajet Power by looking at the pictures and what you´ve found by opening the carb. . You´ll have to measure the whole recipe and verify what you have NOW. Compare with factory specs and then make the proper modifications for your new engine.
I recommend getting Cliff´s book on Quadrajets for starters.

[Kenth]

Originally Posted by srmmmm

Finally had a chance to take in some of Cliff's experienced recommendations and did a careful reassembly of the carb. Three discoveries along the way: 1) wrong base gasket (left side of picture), 2) float height was set at 5/8" instead of 5/16", and 3) float pivot pin protruded above the level of the float bowl casting lifting the float bowl gasket and potentially binding the main metering rods.

It's back on the engine but waiting for daylight hours so I don't wake the neighbors when I start it.

1. Flange gasket to the left is correct for 1971 Buick units. Gasket to the right is for 1965-69 Chevy intakes which needs a steel shim on top of it.
2. Correct float setting for 7041242 is 13/32".
3. The slightly protruded float pivot pin is pushed down by the airhorn, with gasket in between, and holds the float in secure location. There is NO way it could cause binding of the primary metering rods.

7041242 uses #75 main jets with 45B primary rod, AV secondary rods and #7011957 power piston spring from factory.

FWIW

[srmmmm]

Originally Posted by Kenth

1. Flange gasket to the left is correct for 1971 Buick units. Gasket to the right is for 1965-69 Chevy intakes which needs a steel shim on top of it.
2. Correct float setting for 7041242 is 13/32".
3. The slightly protruded float pivot pin is pushed down by the airhorn, with gasket in between, and holds the float in secure location. There is NO way it could cause binding of the primary metering rods.

7041242 uses #75 main jets with 45B primary rod, AV secondary rods and #7011957 power piston spring from factory.

FWIW

Thanks for the observation on the float pin. I'll correct that condition. The jets, rods and hanger combo in the carb matches the Ram Air III which I though would be a better place to start at with my 413 ci displacement and XE276HR cam. I do have all the ones you mention though on hand.