Stalls with A/C on

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Ricks70Duster340

Ricks70Duster340

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I have a 360 with performer manifold, headers and an AVS-2 650 carb. Engine runs fine otherwise but when the car is stopped in gear and the A/C is on, if I blip the throttle the engine stalls. Idle RPM is about 950, 800 in gear, and about 675 with the compressor on. I recall way back that cars had a solenoid that kept the idle RPM up while the A/C was on. I don't have one of those.

Thoughts?
 
Well don't blip the throttle

Make sure you have enough timing in it, and that the idle mixture is not too lean

Another solution might be (I can't remember the name) a throttle damper pot. l They look like a little vacuum can, and when the throttle comes back down to idle and rests on them, they gently let the air out of the pot and lower it down gently

Seems to me Ford used to use them a lot
 
67Dart273 said:
Well don't blip the throttle

Make sure you have enough timing in it, and that the idle mixture is not too lean

Another solution might be (I can't remember the name) a throttle damper pot. l They look like a little vacuum can, and when the throttle comes back down to idle and rests on them, they gently let the air out of the pot and lower it down gently

Seems to me Ford used to use them a lot
Click to expand...
Funny! Blipping the throttle is common in driving. Just had the car aligned and the tech kept stalling it as he tried to get up the ramp.

Will look into that.
 
what cam, or
how much cylinder pressure, and
how much idler timing.

Most guys think they have to have race-car timing at idle. Invariably this closes the transfer ports, so that just messes everything up.
Take your carb off, flip it over and with the choke NOT on, open the throttles until the transfer ports are exposed from square to a lil taller than square. Reinstall it and DO NOT TOUCH THAT CURB IDLE SPEED SCREW. Reset the mixture screws to in the center of their normal range, which on a Carter-type carb is ~2.5 turns out.
If your cam is smaller than [email protected], close the Secondaries up tight but not sticking.
To adjust the idle-speed use Idle-timing.
For idle quality, you may have to introduce by-pass air.
This assumes that the only air that the engine is getting, is coming in thru the Primaries and the PCV system
 
89on35s said:
This is what I used for a very similar problem using 750 QFT double pumper. I searched for a cheaper alternative but didn't find it, not saying it's not out there.

The solenoid energizes when the AC clutch energizes.

Cley
Holley 46-74 Holley Universal Throttle Solenoids | Summit Racing
Click to expand...
OP don't limit yourself to Mopar. I know not the quality, but found this one for 40

www.lectriclimited.com

CARBURETOR IDLE STOP SOLENOID - Lectric Limited

-O.E.M. replacement made in U.S.A.-, V8
www.lectriclimited.com www.lectriclimited.com

Another, just under 55


I Google searched "carburetor idle solenoid"

NOTE that "idle stop solenoid" is not same thing. They cut off fuel when key is shut off "Idle cutoff"
 
I got the Demon 1950 idle solenoid. I used en Edelbrock 750 with it for a very short time. I did have to slightly bend the throttle lever out just a little so the stop would make contact. No biggie. The 750 didn't work out, so the street Demon went back on. The solenoid was about 150. None of them are cheap.
 
An engine of that size should be able to handle the extra load of A/C. I would try richening the idle mixture screws slightly.
 
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