62 dodge .060 over 383 inline dual AFBs, car simply will not run smoothly when colder ambient temps arrive. Runs great in summer time but in fall and winter when approaching 3000 rpm starts severe stumbling and falling off.
Any ideas

 

Welcome.

My first guess from your description would be carburetor boosters are icing up.

Do you have heat cross over open and a hot air into the air cleaner inlet?

 

Hmm never thought of that. I have also been told that cold weather may call for different metering rods. Hope not. Don't want to do that every time there is a weather change. I'm familiar w carb icing in airplanes so I know it does happen

 

Ray -

More familiar with Holleys, but a lot of people do different tunes for summer and winter, especially on car without chokes.

Archer

 

how cold of weather?

 

Couple question before I threw in my 2 cents......

The car is fully warned up to operating tempeture when this happens?
Chokes fully opened on both carbs?
It happens all the time in cooler weather... All the time ?
And lastly... Are the AFB set up as progressive throttle or are both carbs set up to work all 4 butter fly's at the same time?

 

The car is fully warmed up. I actually went to a hotter thermostat on that same theory. The car has a single choke and progressive linkage. When the ambient temp drops to 60 or so the car starts to behave like that. The colder it is the worse it is. I appreciate all the input guys it's not long til cooler fall weather here.
Ray

 

My 2 Cents.. While I dont disagree with what the other guys are saying.
"Their Awesome !!"

I think the motor is just running rich around that time of year. The cam profile and the fueling arrangement are just not getting along... That is more the reason for the suggestion on the rejetting......

My suggestion is to add 8* of timing and reset the curb idle and see if that Does the trick for winter...

If that doesn't work then a little deeper look might help.... Sometimes it is as simple as increasing the heat range of the plugs...

Also As for the thermostat... I myself like 180* with a 16 lbs radiator cap.
But with that said... I am also in SO-CAL..

Keep use posted on what you find..

 

I tend to agree that it's a mixture issue .
Thanks everyone
Ray w

 

Crappy Ethanol gas