Quadrajet Problem Solving > Diagnose a Quadrajet carburetor problem

More nozzle drip big block 427 chevy

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chasrahm:
I bought Cliff's book in 2011 and some parts from Cliff's in January 2012.
The drivability of my Corvette is excellent from loaded in too high of a gear to WOT, car drives very well.  And it is very fast.
However, the exhaust note at idle is  very heavy and idle mixture never smells right.
After reading in the book and on this forum, I have nozzle drip.
First, I added back (unplugged) the idle bypass.  It helped, but not there yet.  Throttle stop screw is only half turn after contacting linkage, but I have drip.
The engine has high, even compression at 165-179, and could have a more aggressive cam, I don't know.

Recipe:
Idle tube .035
Idle channel restrictors  .046
Idle bypass. .092
Lower idle air bleed. .070
Upper idle air bleed  >.078 but <.093
Accel pump discharge .070. (Error?  I drilled these in 2012 and think it is wrong)
Main air bleed body. .070
Main air bleed horn. .070
Main jet. .071
Primary metering rod. 42B
Fuel inlet seat .125
Float level. .325

Thoughts?

chasrahm:
In addition, my mixture screw openings are 0.90"

77cruiser:
Do you have hole in the throttle plates? What's the vacuum @ idle? Does it flood at all on a hot start?

chasrahm:
No holes in throttle plates.

Starts well when hot.  Hot or cold, I always have to pump the pedal a couple of times to prime engine with fuel, which I'm told is normal for a big block engine.

Vacuum at 650 rpm idle is 13-14.

chasrahm:
What about my primary metering needles and the piston rod situation?
Could the spring below be too strong and not pulled down at idle?  Could this cause nozzle drip?
How to test my piston action?

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