I need some help with my 69 383 automatic A/C Road Runner. I am having trouble with the car stalling when it comes to a stop when warmed up. I have changed gas tank sender, line, fuel pump, filter, and new Edelbrock 1405, choke deleted because of warm climate. I found that the timming chain had a 10 degree stretch, so I replaced it and at the same time installed an Edelbrock Performer intake and aluminum water pump, recored the radiator. I found that the vaccum advance was inoperable on the points distibutor, so decided on a Pertronix Billet distributor and flame Thrower 3 coil, new wires, 65 amp alternator, an electronic voltage regulator, but run it through the ballast resister, because it runs really bad if I don't. When the car is warming up it runs good, but as it gets warm it starts to stall when slowing down or stopped, amp meter drops negative. when I load it with lights and A/C it gets worse. After it stalls it fires no problem, but starts to stall when I put it in gear. I switched out the Pertronix with a good points ditributor, but same thing. Timming is at 12 btdc at 750rpm. It seems to be elctical but not sure where to start. I know all my grounds are good......hope someone can help shed some light on my problem.....thanks.

Take out the idle mixture screws & afix one of those thin red straws that come on a WD40 can to a can of Brake Kleen & shoot a 2 second blast into each port. Count the # of turns in to lightly seated so you can easily return the screws to their original position. Might have a vac leak. E10 (ethanol) will make it want to stall when hot

Thanks for the advice...for sure I don't have a vaccum leak, one of the first things I checked after i changed the intake..and I've done the shoot out of the mixture ports....i will look into the rotor phasing....thanks again

You're way ahead of me! Holler what it ends up being. Got another coil on hand you could sub in for a quick test? But it kinda sounds like fuel

I have done the change with a good Accel coil with no differance...but will definitly look into wether the carb is getting enough fuel, though the see through fuel filter is at least 1/2 full while running...thanks.

How many turns in does it take to lightly seat the idle mixture screws?

I find Edlebrocks tend to like the idle mixture screws around a 1-1.5 turns out from lightly seated.

And to that, how big is the cam in the engine, because it's possible it may need more RPM than 750 for idleing. 750 RPM at neutral idleing may not be enough for when it goes into drive. Do you know the in gear idle RPM?

Also a super tight converter on a biger cam will really drop the RPM in drive and make it very hard to drive around the idle range---for example a small block with a stock stall 904 converter fighting against a mopar 292 / 509 purpleshaft cam. This an example of one I worked on for someone else. The car was then speced for a 3600 stall converter by a well known company and all the other drivability issues disappeared.

From what the paperwork says when I bought the car, the engine was rebuilt to stock specifications in 2005, by a shop in california, but when contacted they don't keep records going back that far, but by the way the car ran when I first got it, it is stock, no cams, and such.
As for idle, I have had it up to 900, it will still stall. Idle mixture screws are another matter. right now I have both at about 2 1/2 to 3 turns out for the smoothest idle at about 16 to 17 in. of vaccum.

whats your fuel pressure? those edel carbs don't like alot of pressure 6psi is plenty

I'm running a Carter 6903 which should put me right in the ballpark for fuel pressure for this carb.

Anyway you can get a gauge on it to be sure?

I have a friend that races and has many times seen pumps NOT put out what they were supposed too---most were over spec. I have my Eddy's set at 5.5 psi for the moment until I can dial it in better. Sometimes you can go more, sometimes not, always best to be sure.

I installed a fuel pressure gauge tonight after i got home from work, will evaluate tommorow when i get home, and post reading.

Fuel pressure when warmed up was 6.5 psi. It was idleing at 750 to 900
slowly jumping between 16.5 and 18in of vaccum, then it would go to 19 in of vacuum at 900 for about 20-25 seconds steady, then go back to varying between 16.5 and 18 in vac. It seems everytime I try to drive it it has a new symtom.

You may have a case where when driving, it is calling for fuel and the needle and seat is open, but when you let off, and the needle and seat are most likely trying to close at or near that point, you mayy just have a hair to much pressure do to a spike in the fuel system and forcing fuel past the needle and seat, and then out the venturies thus momentarily flooding the car.

It would be nice if you could at least put a temporary regulator on it to lower the pressure just a little bit. If you had a holley on it, that pressure would be just fine.

First thing I would do is check the float levels in the carb

Thanks for the advice, will check the floats and see if I can rgulate the flow.....will post results when done...

Took the top off the carb, and surprise, one of the floats was hanging lower than the other one...reset the float, cleaned the bowls, took it out for a drive and it runs better, and didn't stall.
The problem now is when going up a faily steep hill the transition from slowspeed to accelerating seems to bog down until more gas is applied, about 1/2 to 3/4 push on the pedal then it picks up.... maybe a spring change on the metering rod I'm thinking....will post results...

Tested the new set up....pink spring for metering rods totally eliminated the hestation problem...yay! but still having the stalling issue...boo! Regulated the fuel to 5psi, no affect, so I'm going to go in and check the floats again. Idleing at 800, with 20 degrees advance, 18 inches of vaccum today. If I back down the advance to say 15 or less the engine wants to not idle and stall. It seems to run ok with no accessories on but if the a/c turns on its definitly going to stall....getting pretty frustated...maybe thinking of going to another carb....