Need Idle help-Newly rebuilt with cliffs parts

[wj3v]

Motor specs:
454 bored .100 over
300CC oval port aluminum heads  119cc chamber
Weiand dual plane intake
8.5 compression ratio
Cam Specs   Duration at 050 inch Lift: 211 int./230 exh.    Lift  0.510 int./0.540 exh roller cam

Carb Info:
17084226  Rebuilt with kit from Cliff. He supplied new main 74 jets, Primary rods 50C, and DA secondary rods. I also installed and drilled new idle tubes to 0.037. Also per his advice carb is setup as follows:
MAB 0.087
IAB  0.068
Bypass Air  0.100
DCR  0.055
Lower Idle air bleed 0.078

Problem is idle wanders. If I put my hand over the choke in just the right way idle smooths up nicely. Vacuum at idle is 14" but when I cover choke it rises up to almost 16" and smooths out. Also I don't have much control of the mixture screws. The passenger side screw when turned all the way in will stall the motor. The other side doesn't have much if any effect at all.

I am running this motor on a motor stand and trying to get the bugs worked out before I put it in the car. Any and all advice is appeciated.

[77cruiser]

How much timing do you have?

[wj3v]

14 initial with vacuum canister hooked up to manifold vacuum. I think, but can't remember for sure, total at idle with manifold vacuum was around 32.

[77cruiser]

No vacuum leaks?
What did you set the float level to?

[wj3v]

Pretty sure there are no vacuum leaks. Everything is capped off that's not in use. Only have distributor and vacuum gauge hooked up. Thought I had wrote down the float level but can't find it and don't remember what I set it at.

[77cruiser]

Is the body to base gasket correct? I had one that had the wrong gasket & had similar symptoms.
How far did you turn the screws out? Did you open the idle mixture holes a bit?

[wj3v]

Answers below in red.

Is the body to base gasket correct?
As far as I can tell its correct. But if needed I will take it apart and take another look.
 I had one that had the wrong gasket & had similar symptoms.
How far did you turn the screws out?
Tried from fully closed to all the way out.
Did you open the idle mixture holes a bit?
No I did not

[Cliff Ruggles]

It is wanting more idle fuel if it smooths out when you place your hand over the choke area or "tip-in" the choke flap to richen things up.

Open up the holes under the mixtures screws to .086-.089".

Turn the mixture screws out about 5-6 turns and work from there.

What LSA is the cam ground on and where is the ICL set at?  That's a small cam in a 454 build and pretty low compression for aluminum heads.  It may simply want more idle fuel to be happy........Cliff

[wj3v]

Cam spec:
Cam # 24502611   454HO roller cam
@   0.050
ID   211
ED   230
LSA   112
ICL   108

IVO   -2.5   BTDC (- indicates ATDC)
IVC   33.5   ABDC
EVO   51   BBDC
EVC   -1   ATDC (- indicates BTDC)
ECL   116
Overlap -3.5

I'll try opening up the mixture screw holes and see what happens. Probably won't be able to work on it until the weekend.

[wj3v]

Had a chance to work on this tonight.
 I opened up the mixture screws to .092  They were .059.
Also opened up the the idle down channel to .058

Really improved the idle quality. Now has steady vacuum of 16" at 800 rpm. Can turn idle screw all the way out and still idles at 450 rpm.

Still have a few questions. I can screw the mixture screws all the way in and it still will run. They do have a slight effect but even with the throttle blades closed I would think it would stall out but it doesn't.

Also, if I remove a vacuum line the idle will speed up now. Maybe this is normal?

I also think I may need to put bushings in the base plate for the throttle shaft. I sprayed some carb cleaner there and it definitely made the idle even smoother.

Making progress on this has been very encouraging. I was amazed at the difference it made just opening up the idle circuits. 

[Cliff Ruggles]

If the idle speed slows down when you turn them in it's good enough.

No big deal if you can't kill out the engine seating them as some fuel still comes from the exposed transfer slots and the screws may be coil binding on the springs under them and not cutting off all the idle fuel.......Cliff