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Glad to be here with Mopar folks, Earl...

Earl

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Hey guys, I'm an older guy with a couple of AARs. One of them in driving me crazy and I could really use some help. As you know these cars are small block, 6-pack cars. The problem car is timed to spects and starts and idles great. When it is put in gear, automatic, it shakes and wants to stall.... Thanks, Earl
 

BriceRoad

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Welcome aboard Earl!


Possible vacuum leak? Is the first thing that comes to mind. I know I had a car that did that back in the day but I can’t remember what the cause was. Is the vacuum advance hooked to ported vacuum? Keep us posted.
 

BriceRoad

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Are your spark plugs and wires in good condition? How about the firing order? Is that correct? One time I mixed up the wires going to cylinder 5 and 7 on a 318 and it had a similar problem.
 

fasjac

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Welcome from Arkansas! Glad you’re on the site. Did it just start acting up on one start and drive? Like to know more details. Theses guys here can solve the problem. Just need some info. And share some pictures when you have time.
 

Earl

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Its been like this for awhile, always rough when in gear and great idling when in park. Wires are correct and vacuum lines are fairly new. I do appreciate any and all help with this problem....

Cuda Motor1.jpg


Cuda Motor2.jpg
 

340challconvert

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Earl
:welcome: to FEBO from New Jersey
It does sound like a possible vacuum leak. A small leak could cause a stumble at a low rpm, especially when in gear on an automatic trans.
Make sure the vacuum lines are all hooked up correctly. I once had this problem with a damaged intake manifold gasket causing a vacuum leak. A damaged spark plug or wire could also cause this symptom.
Worst case scenario I have seen was a single bad valve. I would also do a cylinder compression test. JMO
 

fasjac

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Where to start? have you measured vacuum recently? Sprayed around for vac leaks?
 

340challconvert

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Also, my recollection of the vacuum lines from my old 440-6; the line at the center carb base plate goes to the dash pot. The line at the side/metering plate to vacuum advance and the nipple in the middle goes to the outside carbs.
There should not be constant vacuum pull to the outboard carbs. It has been a while for me on this. I would pull up a factory diagram.
 

Chryco Psycho

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Hi Earl & welcome to the site .
With todays fuels the factory specs do not work well , bring the initial timing up to 16* with a total of 36* & it will run far better , 5* at idle is not enough to run well
 

Earl

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Thank-you guys for responding... I truly appreciate the feedback... Here's what I have tested so far, I did advanced the timing but, still had the rough running in gear asit idled. I vacuumed tested it and found it was poor/fair. I did a compression test, non-running and found 3 cylinders low. I did a RPM test for each cylinder, killing the cylinder and found 3 cylinders not responding. Next I'm going to do a running compression and a cylinder bleed.
 

Earl

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Just finished the cylinder bleed test, the results are that the rings are dropping pressure over 20%. Do any of you North Texas guys know a good reliable mopar engine builder?
 

CMC

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I know one down in the houston area. Guy has 35 or 40 years of experience and just moved there from Southern California. Look up restorations by Julius and give him a call
He did 2 of my motors...
 

fasjac

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I'm going to do a running compression a[/QUOTE]Wrong post.
 
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