440 dies at idle (in gear)

[Plum70Dodge]

440 284/484 cam. hipo ex manifolds. New edlebrock 750 that was a manual choke, but I installed an electric choke on it. 727 trans with new 2400 stall convertor.  15-16 inches of vacuum. 63/47 rods and pink springs.

This car runs fine at speed. perfect even.
When you idle at a stop light too long (3 minutes) with a fully warm engine (in gear)
it will surge a bit, and then die. Starts right back up. If I take it out of gear this is never a problem.
Not overheating. Runs 165 all day. Just replaced the intake gasket/valley pan. no change.
recently:
Swapped two different carbs.
Swapped ECU and coil with same results.
Bumped the timing up to 16* initial and 42* all in.
Runs a but better now, and takes longer for the surging to begin, but will still eventually die at idle in gear.

[greentween]

Block vacuum advance off and try it.

Power brakes: - Try parking brake at a stop instead of brake pedal. Any difference? Booster leak?

At a stop in gear are the needles in the carb still sucked down, or are they dancing up/down?

[MoparLeo]

What is the idle speed with the car in gear ?
165° is not the proper engine temp. Too low. Should be 195° factory. 16lb radiator cap and 50/50 distilled water to proper type coolant mix ratio. Also make sure that the vacuum advance is re-connected after you adjust the carb for max, steady vacuum reading.

[Plum70Dodge]

Yes, tried it with and without the vacuum advance.
Blocked off brake booster no change.
Checked the metering rods. They are down at idle and stay there until i really give it heck (near wide open throttle.)
I did notice that my pcv valve was running a like a sewing machine, but that stopped when i advanced the timing a but and gained and extra 1 or 1.5" in vacuum. 

i'm shooting for idle around 850-900 rpm in neutral.
I would like it to hold steady around 700 in gear. It slowly fluctuates until its down around 600 then it dies. 

[Plum70Dodge]

moparLeo

I was wondering if that may be running too cool. Thanks. I just got the engine set up with A/C and am planning on a long trip. I didnt want to overheat so I used a 160* thermostat. but i dont think this is the problem as the surging doesnt happen when the car is cold. It needs to get up to 160+

[moreparts]

You have verified there are no vacuum leaks, right?  I'd also double check the connectors at the firewall to make sure none are burnt, loose, or have become unseated.  Also have a look at the main connectors under your dash while you're at it.  I've seen slightly loose connections make for some really tough troubleshooting.

[Plum70Dodge]

thanks moreparts
i capped up all the vacuums so Im pretty sure its not that (although that seems most likely)
I will check my connections next. (all new harnesses in the car)

[JH27N0B]

Probably not your issue but I had a similar issue with my car the other day, which has always run great before.
I store my cars for winter with a full or nearly full tank. This car was in MCACN in November and the convention center regs say no cars on display can have over 1/4 tank. 
Afterwards on thanksgiving weekend I filled up and added Stabil before putting it into winter hibernation.
I've only had the car out a few times this season, and yet to need gas.
I suspect that my late November fill up was crappy winter blend gas, and now is boiling in the carb bowl and lines and that is why the car gave me grief after sitting there getting hot.  Driving at speed it's still running great.
I need some chilly weather where I can go for a long drive to burn up that crappy gas, and then put summer blend in! 

[Chryco Psycho]

Mechanical fuel Pump , was the pushrod checked or changed lately ?

[Plum70Dodge]

I did change the fuel pump recently but not the push rod.
When the car does die, I have to press the gad pedal once and hold it down to start the car.
Usually starts within a couple seconds of cranking.

[chaps70rt]

I had the same issue on my 440 with the original push rod for the fuel pump.   Swapped it out as the hardened end was worn.   Problem solved.