Quadrajet Problem Solving > Diagnose a Quadrajet carburetor problem

Qjet Hunting at idle

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buicksstage1:
I have a Buick 470 stroker, 4.350 bore/3.950 stroke, 10.5:1, Sgt2 SE heads that flow 350/240@.600 lift, Cam is a HYD roller 230/23 @ .050 112 SA .550/.571 lift. 2 inch header, single plane intake and Q950 carb and it made 650hp @ 6100. I am guessing its making 600hp ish now that  I changed the Intake to a Eddy B4B dual plane and a 7042240 Qjet which has Idle bypass air holes. I Used the Third Recipe out of Cliffs book which is a really good book if you do not have it yet. Problem I am having is its hunting @ idle 300 rpm ish. No vacuum leaks, throttle plates look good for position on the transition slots. I pulled the front metering rods out just to see if it would change it and it seems of maybe made it a bit better but still doing it.  Any idea's?       

buicksstage1:
Bad keyboard sorry.   230/238@.050

Cliff Ruggles:
Are you seeing any nozzle drip at idle?

Exactly what has been done to it:

LIAB
UIAB
Bypass air (baseplate or throttle plates or both)
Jets
Primary Rods
MAB sizes
N/S size
Float level
Fuel Pressure


....Cliff

buicksstage1:
Did I screw it up lol? This is a street car that will be drive but is there a better direction for that kind of power other then a holley?                                                                                                                             Idle tube restriction,             0.038
Idle down tube,                    0.062
Upper Idle air bleeds            0.068                                                                                                 
Lower idle air bleeds ...........0.070
Acc. pump discharge holes,   0.028"
Idle screw restriction,           0.095
Main air bleeds,                     0.070
Primary jets,                          0.075
Primary rods,                         0.041
Fuel inlet,                               0.145
Float level,                             0.250
Secondary well restriction,     0.040
Secondary POE restriction,     0.062
Secondary tube restriction,    0.038
Secondary rod hanger,           0.545" (G)
Secondary rods.                     0.410 power tip

buicksstage1:

--- Quote from: Cliff Ruggles on April 09, 2018, 05:00:45 AM ---Are you seeing any nozzle drip at idle?

Exactly what has been done to it:

LIAB
UIAB
Bypass air (baseplate or throttle plates or both)
Jets
Primary Rods
MAB sizes
N/S size
Float level
Fuel Pressure


....Cliff

--- End quote ---
I might have it sorted out.

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