Miss and carb tuning troubleshooting

[alindeman1989]

Hey all, I have been reading thread after thread trying to narrow down some of the issues I have and took in a bit too much information and need some help to get me in the right direction before I start tearing it apart this weekend so I'll lay out the problems at hand.

73 Scamp specs:
-318
-eddy performer intake
-eddy 1406 carb
-long tube headers
-2.5 in exhaust
-Trailbeast's HEI and distrubutor
-NGK BKR6E spark plugs
-possibly some unknown rv cam, has a slight lope at idle
-initial distributor timing set at 15 btdc, total 35 @2500rpm, vac advance can set at +15

So I'll start out with the miss, at idle, part throttle acceleration, and wot there is no apparent miss at all, but at cruise in town/freeway or free revving the motor up past idle at a constant rpm, there is an audible "pop" coming out of the passenger side exhaust. Has anyone experienced a similar issue? Leaking intake manifold gasket? Burnt valve? Not sure.

*Edit* Also, if i get on it pretty hard, and let off the throttle to coast, the back firing becomes more apparent, if that helps at all.

And the other thing I am dealing with is how the carb is running. Currently set at 1 stage richer in cruise (to see if that would get rid of the miss) and using the silver springs, going to go lower to possibly see if helps the issue. I have been monitoring on my wideband this past week on my commute to work, idle afr is at about 15-16, cruising about the same under 35 mph, but as soon as the rpm's go a bit higher cruising at 60-65 mph, afr is at about 14-14.5 (which is what I want below 35 haha). Springs might have something to do with this, thinking not having enough manifold vacuum at 2500 rpm cruising on the freeway to keep the rods down? I was under the impression the afr shouldn't change much if the rods are down at cruise even at a higher rpm, if that's the case, change the rods cruise mode one stage more rich and softer spring to balance it out no? And the final issue I have is lightly tipping into the throttle to accelerate, afr is around 14's, but any sort of not so light movement to get up to speed/half throttle/wot the carb just dumps fuel, afr hitting 10-11. Stock fuel pump (fairly new replacement) pressure sending too much gas to the carb? Float adjustment? I don't know, but will reset everything this weekend. Every post I have seen about issues with this carb seem to be off idle stumble or lean bog conditions when flooring it at speed, I have the complete opposite of this issue and she gets up an will spin the tires off as soon as I peg the gas.

So those are my woes, I have on the way a rebuild kit for the eddy, a fuel pressure regulator to limit the fuel to carb to about 5 psi as per spec, 1/2" wood carb spacer because sometimes is takes a sec to start when hot, (**** california gas evaporates too easily). I gave my input on the things that I think might work and what the issues could be and you guys will probably school me about HAH! Hopefully I'll get something out of it, I get the basic concepts and all and am having a fun time learning, tuning, and seeing what others have done in their experience.

 

[rustycowll69]

compression test? leak down test? plug reading?
I like the spacer idea. I like the carb kit, because the needle and seat may be leaking, especially when hot. Immediately after hot shut down, look down the primaries. Do you see any wisps of smoke rising up, or a fog of vaporized fuel. That usually means worn needle and seat, and/or too high float level.

 

[swies]

 

[alindeman1989]

compression test? leak down test? plug reading?
I like the spacer idea. I like the carb kit, because the needle and seat may be leaking, especially when hot. Immediately after hot shut down, look down the primaries. Do you see any wisps of smoke rising up, or a fog of vaporized fuel. That usually means worn needle and seat, and/or too high float level.

Compression test is due this weekend and will probably tell me a lot haha. Will probably get a leakdown test kit when I am at the parts store too as I have been meaning to get one for a long while and have a compressor now. Plugs, last time I checked had black carbon around the ring, spanned down about 2 threads, porcelain was somewhat white with light black tinge from what I remember, no idea as of now, but same symptoms then. I'll pull the filter off and check out for smoke when I get home from work while its hot and report back. Thanks!

P.S. Working on cars at an apartment with no lighting in the dark sucks, needa find a new place with a garage!

 

[seabee]

Have you put a vac gauge on it?

 

[alindeman1989]

Have you put a vac gauge on it?

Last time I checked, at idle it was pulling about 18-19" Haven't tried seeing what it does while driving though, might be a good idea, thanks.

 

[AJ/FormS]

Q1,Are your exhaust pipes shared between sides?

I'm going with a bad header-flange gasket on the side that pops.
At closed throttle decelleration, the headers will pull a vacuum at the flange, and if the AFR is rich,or the ignition timing is late,the still burning gas mixes with the fresh air being sucked in by the header, and explodes, causing a pop in the pipe. If the exhaust was dropped you would probably see flames coming out of the collector.
This is more apparent under compression braking as the engine draws excessive amounts of fuel past the not-quite-closed-enough throttles.So that leads to the question,
Q2) what is your idle speed? and Q3) have you synced up your Transfer ports?What Champion heat range does your plug crossover to? I run Champion RN12YCs, IIRC, 12s are fairly cool. Your engine might like 9s.
So to recap; get your T-port synced up, hoping to set the idle closer to 650/700 in Neutral, Put the carb back to stock,and fix the header-flange leak. If you have an IR gun, you might be able to prove the leak. It will be the tube that runs the hottest about 2 to 3 inches from the flange. It will be at least 100 to 300 degrees hotter than the others. It runs hotter cuz the gas is burning in the pipe.
Good luck.
BTW
Once the T-port sync is established, do not mess with the speed screw! Don't be surprised if it takes less initial timing to slow the engine down. 15* is, IMO, too much for a cam that idles at 18/19 inches. I think 10 or 12 will be better. Getting the transfers synced at idle is job #1.
For help with this click on the little blue M below, or go visit the Holley site.

Also,IMO 35* at 2500 is too much . But if it doesn't detonate then I guess you are alright. I just know that I would not run that much. Then again,I run 87E10, in my 10.9compression 367cuber.
Q4) What stall are you running?

 

[rustycowll69]

Last time I checked, at idle it was pulling about 18-19" Haven't tried seeing what it does while driving though, might be a good idea, thanks.

is the needle steady? you say 18 to 19", but at what idle rpm?
I agree with the suggestion to look for an exhaust leak, that could be a source of the popping noise.

 

[alindeman1989]

Q1,Are your exhaust pipes shared between sides?

I'm going with a bad header-flange gasket on the side that pops.
At closed throttle decelleration, the headers will pull a vacuum at the flange, and if the AFR is rich,or the ignition timing is late,the still burning gas mixes with the fresh air being sucked in by the header, and explodes, causing a pop in the pipe. If the exhaust was dropped you would probably see flames coming out of the collector.
This is more apparent under compression braking as the engine draws excessive amounts of fuel past the not-quite-closed-enough throttles.So that leads to the question,
Q2) what is your idle speed? and Q3) have you synced up your Transfer ports?What Champion heat range does your plug crossover to? I run Champion RN12YCs, IIRC, 12s are fairly cool. Your engine might like 9s.
So to recap; get your T-port synced up, hoping to set the idle closer to 650/700 in Neutral, Put the carb back to stock,and fix the header-flange leak. If you have an IR gun, you might be able to prove the leak. It will be the tube that runs the hottest about 2 to 3 inches from the flange. It will be at least 100 to 300 degrees hotter than the others. It runs hotter cuz the gas is burning in the pipe.
Good luck.
BTW
Once the T-port sync is established, do not mess with the speed screw! Don't be surprised if it takes less initial timing to slow the engine down. 15* is, IMO, too much for a cam that idles at 18/19 inches. I think 10 or 12 will be better. Getting the transfers synced at idle is job #1.
For help with this click on the little blue M below, or go visit the Holley site.

Also,IMO 35* at 2500 is too much . But if it doesn't detonate then I guess you are alright. I just know that I would not run that much. Then again,I run 87E10, in my 10.9compression 367cuber.
Q4) What stall are you running?

A1) They are shared, has an h-pipe placed in about 12 inches from the collector flange. You know, you might be right, I don't recall a miss on that side before I put headers on (Dougs), that or it wasn't audible enough to hear with the old quiet exhaust and I didn't notice. There is no leaks I can hear of, but I'll pick up a cheap IR gun at harbor freight to check.

A2) Idle speed is set at 950, in gear about 650.

A3) As far as I know they haven't been synced by the last owner and I have not done so myself, but I will most definitely read up about it and follow your write up. NGK BKR6Es are the equivalent of Champion RN9YCs, so I think I am good there.

Once the T-port is synced I'll check timing and see what she ends up liking better, and I might be getting away with 35 because I throw Chevron 91 in all of my rigs, Cali gas is piss water with all the junk they put in it lol.

A4) Stall is at about 2000 rpm, stock as far as I know.

Really appreciate the response, as this is a great starting point for sure, thanks. I wanna tear it apart right now, but damn I have to wait for the weekend.

is the needle steady? you say 18 to 19", but at what idle rpm?
I agree with the suggestion to look for an exhaust leak, that could be a source of the popping noise.

Needle doesn't move at all at my 950 rpm idle, have to give her a good rev for them to come up at all, in gear I am not sure though as I don't have another head to stay on the brakes while I check. And I hope it's that simple, it's pretty damn loud when I hold the rpm up steady in park vrrmmmmmmmm POP vrmmmmmmmmmm POP vrrrrmmmm POP POP, pretty inconsistent.

Do you see any wisps of smoke rising up, or a fog of vaporized fuel. That usually means worn needle and seat, and/or too high float level.

No smokey here when I checked right after got home from stop and go traffic.

 

[RustyRatRod]

Have you tuned the carburetor to the engine? And I mean TUNED, not adjusted. BIG difference.

The 1406 is an economy carburetor and is likely too lean for your combo.

 

[alindeman1989]

Have you tuned the carburetor to the engine? And I mean TUNED, not adjusted. BIG difference.

The 1406 is an economy carburetor and is likely too lean for your combo.

Tuned? I don't think I would have gotten a 1406, but it's what the car had when I bought it so I figured I'd try to make the best of it as half the people I have read say it works great for a mild 318 and the other half say it always has issues, like my dad, said throw it in the trash and get a holley, problem solved lol..

 

[AJ/FormS]

Comments inside the quote

A1) They are shared, has an h-pipe placed in about 12 inches from the collector flange. You know, you might be right, I don't recall a miss on that side before I put headers on (Dougs), that or it wasn't audible enough to hear with the old quiet exhaust and I didn't notice. There is no leaks I can hear of, but I'll pick up a cheap IR gun at harbor freight to check.
You may also find a carbon splash under or anywhere around the leaky pipe at the header flange, usually one of the center ones.
You need to get a helper with gloves on, standing at the back and cupping the pipes.Then bring the rpm up until the popping starts. The helper is to look for a reverse pulse in the pipe where the pipe seems to momentarily suck the glove onto itself. I know of only one way this can happen; if an exhaust valve is hanging open on the intake stroke. If the rpm gets to be too high,it will be difficult or impossible to perceive. I imagine difficult after 1200rpm, impossible after 2000.

A2) Idle speed is set at 950, in gear about 650. This is way to fast and smacks of a poor T-port sync, or secondaries not being closed.But the 300 rpm TC pull-down has me worried more; It smacks of a low torque engine.
A compression test may point us in the right direction.
A cam with a "little" lope should idle much closer to 700/750, and lose only 100 to 150, going into gear.

A3) As far as I know they haven't been synced by the last owner and I have not done so myself, but I will most definitely read up about it and follow your write up. NGK BKR6Es are the equivalent of Champion RN9YCs, so I think I am good there.
I agree
Once the T-port is synced I'll check timing and see what she ends up liking better, and I might be getting away with 35 because I throw Chevron 91 in all of my rigs, Cali gas is piss water with all the junk they put in it lol.
I have a feeling that 91 is more than you really need. I am more concerned by the 15* at idle. Something is not adding up here. I have rarely seen this mixed up a combination. That is; a very high idle and high vacuum with what could be considered a fairly high 15* of idle timing. Usually the 15*would cause the low-speed mixture screws to go dead when you try to idle it down to normal.
Q5)Are you running a working PCV valve?
Q6) Have you proved the TDC mark?
Q7) are the mixture screws working?
Q8) are the secondaries closed up tight, but not sticking?
Q9) the compression test results? Remember to crank until you see two successive pulses ,about the same, and over 110psi, hopefully.
A4) Stall is at about 2000 rpm, stock as far as I know. Well stock AFAIK doesn't say much, sorry to be blunt

 

[alindeman1989]

Comments inside the quote

A5) Yes, it has a functioning PCV valve, a little noisy though, but I have replaced it 2 times and still the same. Hose isn't collapsed either.

A6) No, tdc mark has not been proven, could explain how the car is running how it is if the damper has slipped.

A7) Mixture screws still work fine. Turning in leans idle afr, turning out richens.

A8) Secondaries seem to be fully closed, will confirm later today.

A9) Compression and leak down test will be done this weekend. I'll post the results. Thanks again.

*Edit* Cold start idle at 950 and only drops to 800 in gear while brake is applied, warm same 'ol 650.

 

[AJ/FormS]

Comments in the Quote

A5) Yes, it has a functioning PCV valve, a little noisy though, but I have replaced it 2 times and still the same. Hose isn't collapsed either.They are usually quiet at anything over 12inches. Is it possible that your vacuum gauge is out of calibration?

A6) No, tdc mark has not been proven, could explain how the car is running how it is if the damper has slipped.Hyup, proving TDC shoulda been done before the timing was ever set

A7) Mixture screws still work fine. Turning in leans idle afr, turning out richens.
Q10)Will it stall if you turn them all the way in?

A8) Secondaries seem to be fully closed, will confirm later today. Very good

A9) Compression and leak down test will be done this weekend. I'll post the results. Thanks again. We'll be waiting, although it might be premature to do a LD,unless the compression numbers are very low, or very uneven.

*Edit* Cold start idle at 950 and only drops to 800 in gear while brake is applied, warm same 'ol 650.OK, now I am confused. Earlier you said; "A2) Idle speed is set at 950, in gear about 650." So just to be sure,please clarify; what is the normal CURB idle in Neutral, and what is the normal fully warmed up idle speed in-gear with the brakes-applied.

 

[alindeman1989]

Comments in the Quote

A5) Vacuum gauge is fairly new, so I would possibly think it is. It's intermitent, at idle sometimes it's quiet, usually at cold start, when warm it does make more noise at cruise.

A10) yes, it will stall.

As for curb idle in neutral is 950, in gear, warmed up, brakes applied is 650. Will double check to confirm on my next reply.

 

[AJ/FormS]

A5) Vacuum gauge is fairly new, so I would possibly think it is. It's intermitent, at idle sometimes it's quiet, usually at cold start, when warm it does make more noise at cruise. If you can hear inside the car while cruising, your mufflers are too quiet,lol.

A10) yes, it will stall. Ok good then.By the preponderance of evidence, I have come to believe that your T-port sync is pretty close. And if that is true, then whatever your idle-timing may be, then it too is close. And if that is true then I would be verifying the engine vacuum with a second borrowed gauge. But at this point,knowing the exact idle vacuum is of lessor importance than the compression test results.

As for curb idle in neutral is 950, in gear, warmed up, brakes applied is 650. Will double check to confirm on my next reply.
One more time; Is the 950 curb idle on the warm engine? going to 650 when dropped into gear?What I am getting at, is to be sure the fast-idle cam is fully retracted to off position. Therefore the 300rpm difference is solely to the the TC dragging it down. And then the next question would have to be; Why is the curb idle so high to start with; is it because if the hot curb idle was at a more normal 750 or a bit less with this cam, that the engine would stall when put into gear? And if the answer to that was yes; then we have a problem.

Something is going on that is not right. A 300 rpm drop into gear is excessive. IMO, either the engine is way down on idle torque,or the TC is not working right. And that is why I asked if you knew the stall, by actually testing it.
If the engine is down on idle power, it will be down on power quite a bit farther up the rpm band, and that could be the reason for your screwed up AFRs. The metering rods have to stay down to about 12 or even 10 inches of vacuum. If the compression is not even or very low, then you will be driving into that 12 inches or less zone all the time. And the M-pistons will be popping up, and then the carb will go rich,maybe too-rich,depending on what combination of rods and jets are in it.
I would actually suggest plumbing the vacuum gauge to manifold vacuum and bringing it into the cabin for a few days. Keep an eye on it to gauge your driving habits, and learn how the popping is related to the gas pedal and engine loading.
But I am most eager to see the compression results. Problems like yours always need a good foundation to work from, and proving the engines health is priority one.
The two basic tests for that are the compression test and careful observance of the vacuum gauge.Popping in the exhaust, if valve related, will show up on the vacuum gauge. If it is an exhaust leak problem, the gauge will never see it. If you were to plumb the gauge into the suspect header pipe, the vacuum gauge would read it instantly.
In any case, I at least, will hang around to see the compression results.

Hey, I just thought of something; where is your PCV plumbed into? Are you on the carb port? or on the intake vacuum-tree?
And just to be sure;the vacuum advance can is plumbed into the spark-port right; the port with zero vacuum at idle?

 

[alindeman1989]

Haha, the car is pretty loud, it's the certain rpms where it doesn't drone that I can hear it.

As for the stall, it does stall at 2000 rpm when I gas the car with the brakes applied, I was just saying that's what I have seen is stock for a factory 318?

Curb idle, yes, 950 rpm on a warm motor, choke confirmed all the way open, 650 once it's dropped in gear. It's been a while since I did the idle, but I remember that's what it ended up being when I set it as per Edelbrock's instructions on setting idle mixture. But I have a feeling if it is reset lower, the car might stall if I put it in gear if curb idle is at 750. Should I try and see? or just leave it as is for now until I rebuild the carb and set it this weekend. Following your T-port guide, what do I go abouts for the idle mix screws?

PCV, hmm, it's tapped off the rear center port on the carb as how it was when I got the car, but there is another port on the front that is the same diameter. Vacuum can is tapped of the spark port on the front lower left of the carb.

 

[rustycowll69]

Haha, the car is pretty loud, it's the certain rpms where it doesn't drone that I can hear it.

As for the stall, it does stall at 2000 rpm when I gas the car with the brakes applied, I was just saying that's what I have seen is stock for a factory 318?

Curb idle, yes, 950 rpm on a warm motor, choke confirmed all the way open, 650 once it's dropped in gear. It's been a while since I did the idle, but I remember that's what it ended up being when I set it as per Edelbrock's instructions on setting idle mixture. But I have a feeling if it is reset lower, the car might stall if I put it in gear if curb idle is at 750. Should I try and see? or just leave it as is for now until I rebuild the carb and set it this weekend. Following your T-port guide, what do I go abouts for the idle mix screws?

PCV, hmm, it's tapped off the rear center port on the carb as how it was when I got the car, but there is another port on the front that is the same diameter. Vacuum can is tapped of the spark port on the front lower left of the carb.

that's where the vacuum port for dist. vacuum advance is on the Carter TQ, so that's probably the same on the edelbrock.
As far as the idle speed, 950 seems a little high. The higher the idle speed, the higher the vacuum, so it can be a little misleading on the amount of idle vacuum. But a non stock cam can force you to raise the idle speed to smooth out the idle. How many turns out from seated are the idle mixture screws?

 

[alindeman1989]

that's where the vacuum port for dist. vacuum advance is on the Carter TQ, so that's probably the same on the edelbrock.
As far as the idle speed, 950 seems a little high. The higher the idle speed, the higher the vacuum, so it can be a little misleading on the amount of idle vacuum. But a non stock cam can force you to raise the idle speed to smooth out the idle. How many turns out from seated are the idle mixture screws?

Not sure how many turns out, but I'll let ya know when I am near my car again.

 

[mderoy340]

I have been monitoring on my wideband this past week on my commute to work, idle afr is at about 15-16, cruising about the same under 35 mph,

You are way to lean.

 

[alindeman1989]

I have been monitoring on my wideband this past week on my commute to work, idle afr is at about 15-16, cruising about the same under 35 mph,

You are way to lean.

That I know, going up the next rod size makes it too rich, 12-13s at cruise and even worse on power than it already is, usually try to aim for 14s cruise/idle in gear. Don't want to keep throwing stuff at it til I rebuild the carb this weekend, reset the floats, and set everything back to stock and go from there. Also have to find out what my compression is and where true tdc is on my damper, can't wait that's for sure.

 

[alindeman1989]

that's where the vacuum port for dist. vacuum advance is on the Carter TQ, so that's probably the same on the edelbrock.
As far as the idle speed, 950 seems a little high. The higher the idle speed, the higher the vacuum, so it can be a little misleading on the amount of idle vacuum. But a non stock cam can force you to raise the idle speed to smooth out the idle. How many turns out from seated are the idle mixture screws?

Idle mixture screws are out 1 7/8 turns.

 

[rustycowll69]

starting position is 1-1/2 turns out, so as far as that goes you're pretty close to recommended.

 

[AJ/FormS]

As always, comments inside the quote

Haha, the car is pretty loud, it's the certain rpms where it doesn't drone that I can hear it.

As for the stall, it does stall at 2000 rpm when I gas the car with the brakes applied, I was just saying that's what I have seen is stock for a factory 318?Ok I get it then, Teeners are listed at about 1750. 340s were 2250.

Curb idle, yes, 950 rpm on a warm motor, choke confirmed all the way open, 650 once it's dropped in gear. It's been a while since I did the idle, but I remember that's what it ended up being when I set it as per Edelbrock's instructions on setting idle mixture. But I have a feeling if it is reset lower, the car might stall if I put it in gear if curb idle is at 750. Should I try and see? or just leave it as is for now until I rebuild the carb and set it this weekend. Following your T-port guide, what do I go abouts for the idle mix screws?
950 is way to high for a cam that could pull 18inches at 700. An engine that pulls 18 at 700, should idle at 700 or even less. (Shoot my 367 only pulls 9 or 10 and I can pull it down to 550 with the clutch. It normally idles at 700.)
So, prior to the carb-rebuild,the first thing I would do is verify the TDC mark.
Then,I would crank the curb-idle down to 700,and check the vacuum.After every change in rpm and or timing, the mixture screws may need to be reset.
Then I would advance the distributor timing until the rpm no longer increases and or the vacuum no longer increases. Then I would reduce the curb idle back to 700. Then I would reset the dizzy again to max rpm/max vacuum, and reduce the rpm back to 700 again. Then I would lock the brakes and put it in manual low, and read the in-gear rpm.This is the optimum idle setting.
>However, it is not always possible with carbs and dizzys to run this optimum setting.Sometimes the T-port sync gets so far off that things go wrong;
Perhaps it gets a hesitation or stumble whenever you tip in the throttle, no matter where/what the pumpshot is set to.
Or, as soon as the engine sees the slightest load it might start pinging.
Or the timing is so advanced that it kicks the starter back.
Or the transfers dry up, and the engine stalls when you put it into gear.
But now at least you have a reference point to work from. And the thing I want to see is how the in-gear idle now compares to the in-Neutral rpm.That's what I would do. Of course the TDC mark needs to be verified first.
Then, as soon as the carb comes off, check the transfer slot exposure. It should be square to slightly taller than wide. Make it so.During the rebuild you may be instructed to back the curb idle screw out for certain adjustments. When you come to the end of the rebuild, be sure to reset the T-port sync.
Then, figure out how to get the curb idle screw back to this setting so that when you screw around with it, you can find it again without taking the carb off.
What I do is count the number of turns (to the nearest 1/4 turn) it takes to back out the screw until the throttle is completely closed, but the tiniest turn of the screw sets the plates in motion. Write it down, cuz you will forget it.
Finally reset the mixture screws to 2.5 turns out, cuz the engine may be hard to keep running with as messed up as I made it earlier.This is a preliminary setting.
Do not mess much with the curb idle speed after this.
Set the idle-speed with timing and idle-air bypass.
Reset the mixture screws as may be required. If the mixture screws need to be closed up to less than 1.5, then the t-ports are too far open, back out the curb idle screw, and try again. If the mixture screws need to be out further than 2.5 turns then the transfers exposure is insufficient crank in the curb idle screw, and reset the mixture screws. The goal is to have the engine idling sweetly at or near 2turns.
The transfers are your low-speed fuel delivery system.
The mixture screws are mostly for idle enrichment.
PCV, hmm, it's tapped off the rear center port on the carb as how it was when I got the car, but there is another port on the front that is the same diameter. When you turn the carb upside down, I think you will see that the PCV should be connected to the front side of the carb, and you will see why; the passage is interconnected to both primaries. And I think you will see that if you hook it to the back, the rear four cylinders will run lean, especially the two rearmost. Oh, and that might be the source of your AFR monkey business. If your O2 sensor is in the merge or near to it, it will get all mixed up. That back port is for the powerbrake booster
Vacuum can is tapped of the spark port on the front lower left of the carb.The one that is dead at idle right?

 

[alindeman1989]

Alrighty, TDC first and then I'll follow along from your notes as well as keeping a spreadsheet of what is done to the carb.

When yo turn the carb upside down, I think you will see that the PCV should be connected to the front side of the carb, and you will see why; the passage is interconnected to both primaries. And I think you will see that if you hook it to the back, the rear four cylinders will run lean, especially the two rearmost. Oh, and that might be the source of your AFR monkey business. If your O2 sensor is in the merge or near to it, it will get all mixed up. That back port is for the power.brake booster

Well ****... Guess we will find out when I get back from work, I'll swap it over before I leave. God I'll feel dumb if it was something that simple, shouldn't have expected it with how out of wack everything was set up when I got the car, no mopar linkage adapter, 2 BBL throttle cable bracket, kick down not set right, throttle only opening about 1/4 the way, vac advance on wrong port, among other things I had to fix, but I didn't think to check the PCV routing.

The one that is dead at idle right?

Yes, timed vac port, no vacuum at idle.

Man, thanks so much, you don't know how much I appreciate it, I'll get back to ya'll tonight.