Help me diagnose - various idle speeds, stalls when cold into reverse

[bsteab0yz]

Hi all -

74 w Blueprint 302 with Edlebrock 4 bbl carb, rebuilt tranny. I don't have a tach, so guessing on some of these RPMs... when I start, the carb seems to high idle fine, let's say around 1500-1800 RPMs. I have it set this high due to some other issues seen below.

Unless I let it warm up for 7-10 mins, when I put it into reverse, it immediately idles rough and stalls. Of note, when it's warm and put into reverse, it's fine. Never stalls when warm. When it's cold, I can shift into any other gear and it does not stall and die. Just reverse. Also of note, if I hold the brake with my left foot, give it gas with my right and put it into reverse, it will NOT die. So, it seems as if it is idling way too low when I put into reverse.

I have also noticed the "park" idle is probably double the RPMs as the "drive" and "reverse" idle.

Is there another setting on the carb that allows me to adjust the idle speed during reverse and drive so I don't have to set the idle screw so high? I assume they are all supposed to be the same... but maybe not? Sorry, not super mechnically inclined.

 

[bronco italiano]

Lots of possible factors.
Since you claim to be not super mechanically inclined, take it to someone that is and you will not be driving yourself insane.

 

[Brush Hog]

So I have a 64 chevelle that does the same thing. I have been told it is a high rpm stall converter that is causing the problem. I don’t know if that’s true or even possible. So I either warm it up for 10 minutes before backing out of the garage or I power brake it out!!!

 

[Broncobowsher]

Sounds like a small vacuum leak that has been tuned around when warm.
What's base timing set to? Probably hard to get it right if you can't get the idle speed right.
Really sounds like it just needs a basic tune up. Get the timing set right, make sure the vacuum advance is on ported and not manifold vacuum. Vacuum leak check (spray flamable carb cleaner around the intake).
If you don't have one, pick up a timing light. For you, get one with a tach built in.