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Ballast Resistors and Mopar Electronic Ignition Conversions...

Some really good suggestions here, however I've run into that issue before and found that my timing chain was worn causing the timing to jump around a bit when it wasn't under load, went away when you squeezed down on the loud peddle. Sounds like a Saturday afternoon and a twelve pack kinda job... Good luck :thumbsup:
Man, I hope not. Engine was supposedly less than 1k miles from rebuilt when I got it,
but who knows?
 
Maybe getting a weak signal to the ECU at low RPM? Check reluctor to pickup gap, and run a ground strap from the ECU to the block.
 
Great ideas surrounding any slop in the distributor/oil pump drive gear and/or slot....
Tell ya what, it doesn't take long to check out, at least rudimentary speaking, so I'm
headed out to the garage to yank the distributor and see what's what there.
Back with a report shortly.
 
Can you confirm the carb # for us

Before I go off , no pun intended , on the off idle to lean mixture on the Edelbrock AFB 1407/1411 750 Carbs that I have worked on in the past

AVS is a completely different model
 
Great ideas surrounding any slop in the distributor/oil pump drive gear and/or slot....
Tell ya what, it doesn't take long to check out, at least rudimentary speaking, so I'm
headed out to the garage to yank the distributor and see what's what there.
Back with a report shortly.


Mine was worn out distributor shaft bushings inside

But that was more of a 4,000 RPMs and higher issue , was very sporadic , drove me nuts
 
Can you confirm the carb # for us
Before I go off , no pun intended , on the off idle to lean mixture on the Edelbrock AFB 1407/1411 750 Carbs that I have worked on in the past
AVS is a completely different model
Here ya go:
IMG_20200622_162405553.jpg
Yes, I stand corrected. I've always had AVS type carbs over the years, but this inherited "reman" one is NOT an AVS.
 
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Ok, video complete. Took distributor out, jiggled this, wiggled that.
The bulk of the "slop" you hear when I have the screwdriver stuck in the oil pump drive
is actually the screwdriver tip rattling around in the gears' slot.
Does the distributor slot in the drive gear look "wallered" to you guys?
The distributor tip itself has dang near no wear indicated on it, looks good and square-
shouldered. It should, since it's not very old....
Anyways, here's the video:
 
Maybe getting a weak signal to the ECU at low RPM? Check reluctor to pickup gap, and run a ground strap from the ECU to the block.
Got a solid "house wiring" copper wire going from the back of the block to the bottom ECU
screw on there now.
Thanks!
 
Well, if anything else, I learned how to combine little snippets of video into one file today,
so there's that... :lol:
 
Anyone? Ferris?
Sheesh, made the video for nuthin'....
 
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Well...the rotor is supposed to have the movement you show, that's the advance mechanism. Reach in with some needlenose pliers or whatever, pull the driveshaft up off of the cam gear, just enough to get the two gears clear of each other, then try to rock the shaft side to side to check for any wobble or looseness. Then pull it out and see how the tip of the distributor shaft engages it. Good time to see if the distributor shaft itself wobbles at all within the housing.
 
Well...the rotor is supposed to have the movement you show, that's the advance mechanism. Reach in with some needlenose pliers or whatever, pull the driveshaft up off of the cam gear, just enough to get the two gears clear of each other, then try to rock the shaft side to side to check for any wobble or looseness. Then pull it out and see how the tip of the distributor shaft engages it. Good time to see if the distributor shaft itself wobbles at all within the housing.
Thanks for replying (and watching)!
1. Well, I was trying not to "get into" the advance in the distributor at all (not get into any of the "felt" spring resistance)
by gingerly just using a couple fingers to move the rotor back and forth, but you can see the jobber thingy under
the distributor plate moving as I did it, so I guess I was into the advance a little?
Yeah, my shadetree instinct told me the movement of the rotor was quite normal.
2. Insofar as distributor tip mating with the drive gear goes, you can feel a pretty firm engagement there when you
install the distributor - there's no slop there, it has to be pretty exactly aligned to go in and when it does, it dang
near clicks in. Since the distributor itself has very low miles on it and I make a point of cleaning the hole in the block
where the distributor mounts, it slips right in as long as the tang on the distributor is exactly aligned.
There is no wobble in the distributor, checked that and again, it's fairly new.
3. Good point on checking the drive gear shaft for slop. It always makes me nervous to go after that rascal in an
assembled engine, but I've had it out before (to align it front-back on TDC like it should be) so it shouldn't fight
much. That'll be my next step, in fact.
Thanks again!
 
Ed, motor is toooo clean, that's the problem! Remember to always check,recheck, grounds is what I say. Otherwise looks normal.
 
Ed, motor is toooo clean, that's the problem! Remember to always check,recheck, grounds is what I say. Otherwise looks normal.
Thanks, but she ain't all that clean. :)
Wrong damn color, too!
 
I am starting to lean towards blaming that "reman" carburetor, to be honest.
 
I am starting to lean towards blaming that "reman" carburetor, to be honest.
I brought that up post #25

Some guys love the 1407/1411 Eddy Carbs and have had good luck with them on Mopars


Not me , and I have tuned many Carter AVS , Carter Competition Series , Eddy AFBs / Eddy AVS

I came across this read some years ago and kept it

Article

https://www.speed-talk.com/forum/viewtopic.php?f=1&t=44392


The clone AFBs, Edelbrock and the previous Federal Mogul versions, have several problems. Many of them (nowadays most) have several reasons they won’t get rich enough on many (most) engines.

The secondary venturi cluster emulsion tube is “pinched” at the bottom with a .073” orifice the fuel must pass through to enter the tube to get up to the discharge nozzle….. and (it gets worse) …… the secondary Main Air Bleed is .073”. Imagine what a Holley would do if it had a .073” bleed in the booster leg.

The reason it doesn’t seem to matter what jet size is used is the .073” air bleed kills the venturi signal and no matter what main jet size larger than .073” is used the fuel must pass through the .073” restriction downstream of the main jet.

As if that isn’t bad enough, the primary MAB (the tube pressed in the top of the cluster) is occasionally very large, .040” or more, and occasionally different on left and right.

Occasionally the idle jet (the small tube pressed in the bottom of the cluster) is different left and right and sometimes the idle jet larger than necessary, resulting in a very rich off-idle.

The 1407 750 CFM uses the same casting for the primary cluster as the 625 CFM carbs in spite of the fact the venturi minor diameter is 5/16” or so lower in the 750 body. This places the exit of the booster venturi that much above the “vena contracta” in the air flow, the result is the “booster signal” is not obtained in the correct location and the metering is erratic, the A/F wanders rich and lean as load and RPM vary as the throttle position is changed.
 
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