Hesitation, stalling - torque converter?

69 Charger 440 RT auto. Fresh, stock rebuild with new Edelbrock 1813 (800cfm) carb, stock points ignition. Starts and idles fine, base timing @12, all in @35. Off idle hesitation before rebuild (with orig AVS), tuning helped but not fully eliminated. Now occurring after rebuild with Edelbrock linkage in the "rich" hole. More recently, occasionally stalls at idle in drive. Starts right back up. Trans has been rebuilt, shifts properly. No unusual sounds (TC clacking/whirring). We didn't change the TC when the engine was rebuilt, so its the original unit. Could the TC be the problem?

It ain't the TC. since it did it on both carbs I would assume the A/P squirt tip in was immediate. a vac leak will do it (vac can/valley pan are potentials) as will E10 gas. Mixture screws out enough turns?

I agree with Rapid Robert

Anyways
"Stalls at idle in drive - Hesitation off idle"



What intake are you running ? Open plenum or divided - Did you check for vacuum leaks ?

Also you mentioned points ignition - How new are the points , and gap/dwell setting ?

When did the problem start with last engine? Was it still stock ignition. I looked at your resto thread again. Is there rust or scale in the gas tank?

Check for a vacuum leak, PB booster, vac headlight system, A/C vacuum lines, etc. disconnect and plug vacuum lines and try it. Accelerator pump system.

What camshaft? What compression ratio? Is it too low now? What distributor and ignition system?


Paid like to see the original carb restored and back on there, edelbrocks bring drivability problems with them esp on BB engines.

We know you do good work, must be frustrating, for now.

I've worked on one of those carbs for a friend who is using it on a 427 chevy. his had the hesitation/stalling thing too. I really changed some stuff around in it to smooth it out. with OOTB calibration his carb would not take off smoothly in first gear (4spd-4.11 gears). after changing things it would take off smoother in 2nd gear than it used to in 1st gear. after a going thru the carb drives and performs well; better than my expectations.


other factors may be timing curve; depending on camshaft. fuel pressure can be a factor too.

There are certainly a lot of things that can contribute to your problem, but the torque converter is not the first item that comes to mind.

The first 2 things that stand out to me with the information provided. A)the initial timing is a little low and the curve is a little slow. And B)the CarterBrocks are often a poor choice given their well deserved reputation for drive-ability issues.

Our big blocks really respond to timing. Throw 5* to 8* more timing at it and try a test drive. No full throttle blasts with that much timing, just a short drive around to see if it helps the stumble.

And see if someone has a known-good carb that you can borrow and try.

Intake is original stock. Have checked for vac leaks, will check again. Points relatively new, dwell setting good.

Problem was evident with engine when we bought it, stock points setup. Tank relatively new. I'll have to dig into the engine rebuilder info to get cam/CR info (daughter/owner has all that). Stock, reman points dizzy, stock coil...replaced failed Firecore all in one installed by engine rebuilder.

VERY frustrating. We've discussed sending orig AVS to Harms. May do that now. Also may upgrade ignition system to Mopar electronic, see if that helps.

The stalling is what made me think of the TC.

We had a problem earlier with a worn fuel pump rod. Gonna check that again as well.

I was contemplating same thing...adding some timing to see what effect it has. My 70RR 440-6 is @ 19base, 35 total, but has a cam and, of course, I can't swap carbs with it

Can you/anyone recommend a better replacement carb until we decide what to do with the orig AVS? I don't much care for the electronic choke on the edelbrock anyway.

Just me I would do a compression test which would confirm the long block (including t chain cam timing/head gasket sealing etc) is Ok if you get good numbers. I'll assume that the dampener ain't slipped (for now) but wouldn't hurt to confirm it with the $10 plug hole 14MM screw in tool. My 1406 600 eddy needed richer jetting from a strip kit on a DD & the elec choke came off way too fast but first what I would do on yours is block the rods up on your carb & see what being on the power circuit full time does for the driveability which might help confirm a vac leak and or lean jetting and or lean choke (easy to do/free/takes little time). EDIT & yes bump the initial up (I have 19 on a bone stock 318)

Bump the timimg. I also have 19 initial. Carb choice is yours but Holleys are stupid easy to tune. 4 corner idle makes it even easier. What's a choke? LOL

As I have said before, our big blocks like a lot of initial timing and the mechanical advance in as quick as the combo allows.

At idle, twist the distributor advanced until it doesn't like it anymore, then just back it up a touch and check the timing. Most will like it somewhere in the low 20s with a mild cam. Hotter cams with rougher idle like even more.

The only limit on the idle advance is if it hits back against the starter when cranked hot. Overall, for a big block, as high an idle advance and as fast a mechanical advance as the engine will take without developing other bad habits.

As long as it doesn't cause other problems, low 20s for idle advance and all in by mid 2,000s RPMs. My current Hemi idles at 25* and is all in by 2,200. Which is about where my wedges end up at.

And I think everyone here knows that I am a big fan of the Street Demon carbs. They are hands down, the best carb out there for a mild street engine. Do a search and you will find a number of threads here on this subject along with links to tests and dyno sessions.

What’s wrong with the original AVS? Is it a 4640? It should be a 750 cfm, equal size primary & secondary throttle plates.

Don’t pile on me for this but I don’t think electronic ignition will help, but it doesn’t hurt to try. Don’t mount the box right away, just bolt a ground wire to it and drive that way to see if it helps.

Hate to drill holes in the new underhood paint job in that nice Charger.

I believe it is a 4640. Butterfly shafts worn. We were having hesitation with it as well.

If it ever stops raining here in No San Diego county, will probably do the timing first, see what happens with that. I kinda agree with you, the electronic conversion probably won't solve the issue.