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any six pac experts out ther

moparstuart

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my super bird convert has a six pac motor the carb are newly remanned by holley

I am having vacuum problems ,( not stopping brakes?weak
we figured out the vacuum sec's are opening really quick and sucking off all my vaccuum on #1 and 3 carb .When at low start up speep when the center carb is all that shoud be working ? Any help ?

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Have you checked to make sure the vacuum lines for the carbs are hooked up properly? Also, what cam are you running? Any idea of how much vacuum it's pulling at idle? There are also different springs for the vacuum pods like for a Holley 4V. Any idea what is in your carbs?
 
Here is something that was posted on another web site about six pack tuning. Hope it helps.

I've been running six pack inductions for about 30 years now, sm blk, big blk, and even the custom 6 pak cast HEMI intake manifolds that I made for the 71 wingcars,.....I don't have anything but, sixpack cars,,,,,,,,I've rebuilt countless numbers of carbs, along with countless installations and tunings,....when there are troubles, it usally due to someone unfamilar with there tuning or functions, or attempts at trying to improve them,......which usally results in "problem" carbs, starting, stalling, flooding issuse!.....seeing your have "new" carbs/ set-uo,....I'd recommend you use a Carter street pump, don't use rubber hose, it's problems down the road!, use a factory style/ repro steel, or stainless steel fuel line kit,a good quality hi flow fuel filter, AFTER the pump!, not before!, you'll restrict the fuel flow, Factory style linkage, no junk progrssive/ mech linkage!, change out the brass side float screw on the fuel bowls (all 3 bowls) with Holleys clear sight plugs, this way you can see your float level, and no gas spills trying to adjust, their like $4 each,.....when setting the fuel level, I've found that it's best to bring it up to half the height of the clear sight plug, (can't do this with the brass sight screw!, unless you have X-ray vision, hence the need to install the clear plastic sights).....plus "if" you ever have a starting problem, just shaking the car side to side will slosh the fuel in the clear site, and you'll know wether or not you have fuel in the bowl,....after you have basically installed the set-up, and started the car, and set an acceptable idle after warm up, with the engine running, set the floats, start with the center carb, the slotted screw on top of the float adjuster, is just a lock screw, you can remove it for now, the 5/8" nut is the adjuster/needle seat nut, rotating it counter clockwise will raise fuel level in the bowl, clockwise will lower it, make small 1/2 turns let the car run a bit, check the fuel in the clear site window, half the window is ideal height, esp. in the front and rear carbs, when they dump in, you don't wanna lean the engine, which on a sixpack car, might "melt" a piston or two!....really!, been, there, done that!....after you set the fuel level in all 3 carbs, reset the idle on the center carb, by disconnecting the linkage on the end carbs, if your using an idle solenoid, make sure it's energized in the up position contacting the center carbs solenoid idle arm screw, set the desired idle, that keeps your car running, factory specs are a guide line, your cam, vacumm, etc, will affect your desired RPM range, after you establish this idle, this is what your car will run with, now de-energize the solenoid, using the idle srew located on the ceter carbs main throttle shaft, set the idle to a bare minimum running idle, this is were your throttle shaft will close down too when you shut off the car, and the idle solenoid de-energizes, if later you have shut down problems of the car desieling, (sputtering run on after shut down) keep lowering the idle screw on the center carb main shaft, untill this is condition is eliminated, the idle solenoid was added to maintain an idle, and allow the throttle blade to choke off the engine on shutdown if needed, when it de-energized, after your center card idle is set, now comes the fun, start the car, in idle, the front and rear carbs are still disconnected at their main throttle linkage, (important note: make sure no vacumm source is hooked up to the front and rear carbs when main linkage is disconnected, cause any reving you may do, might tip in a end carb! with vacumm!, and if you can't shut it down in time, you might lose an engine!....seen it done!)to properly set the fuel/ air mixture idle screws, start with the center carb, hook up a tach.......warmed up, good idle (low)....turn the fuel/ air mixture screws (2) located on each side of the center carb metering block, do one at a time, run it in slowly, until the engine begins to stumble, slowy back it out watching the tach needle, stop when you've obtained the highest rpm reading,....you can also do this with a vacumm gauge attached to MANIFOLD vacumm, I like to use both at the same time, ...repeat the process for the other side, when done, now re-do-it, again, just to confirm settings, now some of the end carbs, have their fuel idle screws "plugged" with lead, they are located in the base, in the front of the carb base plate, under the bowl, if plugged, dig out lead plug, most people think ones for fuel, ones for air , their not!, you'll adjust these screws just like the center carb, except you can't just use a vacumm/ tach gauge,....look into the top of the front end carb, you see 2 small projections in each bore on each side, just below the neck, these are the air bleeds, block off the outer bleed using your finger over the small tiny hole, with the motor running at idle (low), it should stumble or pick up in idle, when you block off, either outboard bleed, set the front carb first, pick a bore, left or right, with it's coresponding baseplate idle screw, block the bleed off with your finger,(make sure the carbs throttle plate is fully closed) do one side at a time, when you block the bleed, if the idle increases, too much fuel, remove your finger, turn the base screw on the side your blocking the bleed on, in, one turn, block the bleed again, listen for the idle, (you could use a tach gauge at this point), if it stumbles/ decreases, no fuel, back the base screw off a half turn, block the air bleed again see where the "idle" is,......keep adjusting in this fashion until there's no change in idle, no increase/ decrease, you now have the ideal fuel/ air ratio for the vacummm requirement on your motor, complete this for both sides of the front carb, shut off the motor, disconnect this carb remove it, re-install it in the rear,....install the rear carb, now in the front, adjust this carb like you did to the last one, after you hook up everything, now here's when most guys will balk at this move,....they'll insist the air/fuel mixture won't be 100% by moving the tuned front carb to the rear, well if your truly familiar with the sixpack set-up, you know getting to the rear carbs base screws is fustrating to say the least, unless your squeezeing every ounze of effeciency out of the motor, this technique is far better than leaving the factory setting/ lead plugs in, with is usally a lean set-up,,,,,,, after setting this relocated carb up, if you wish you can "play" trying to "tweak" the rear carb, this may include a round of removal the "tweak" the screws to obtain that last ounze of "tuning", I've yet to see a "tool", truly capable of fitting into the installed rear carbs "idle screws"......anybody?,

Well, when your "done" setting the air/ fuel "idle" mixtures on the end carbs, connect the end linkages, to the end carbs, do it with the idle solenoid energized, the rods are threaded were they join together on the center carb, they install on the end carbs with rod clips, there is a F/R or left?right handed clip, energize solenoid, do the front carb first, make sure the linkage is pulled far forward on the center carb secondary rail, thread the rod, in or out, until it fits nicely in the hole, then proceed to the rear, repeat this proceedure, now check the linkage for any binding, you should be able to chrack open (engine off!) the center car, WOT, and manually open both carbs by rotating the front carb throttle arm, close the center carb, check all linkage for binding, readjust if needed, now de-energize the idle solenoid, see if any bind is preventing the center carb from closing on the main throttle shaft idle screw, you may have to comprimise on some idle/ and or end carb linkage adjustments to have an ideal, functioning set-up, but once you take the time to do this, you'll appreciate your efforts!,....as far as altering the end carb secondary springs in the vacumm pods,.....I like a sixpack to come in quick,....you'll have to buy 2 sping kits, replace with the "white" springs if you want a quick responding set-up,....if you what a mid range set-up use the "yellow" springs,.....any thing in the brown or black range is worthless.,,,,,
 
Do NOT mess with the idle adjustments on your outboards, especially on a "vintage" set of carbs. More often than not, they will be stuck and you will break off the ends of them trying to adjust them. And that isn't something that is easy to fix.....drilling one out, and trying to retap the passage.

Leave them alone. I've run them for years. Drove a 68 Satellite wagon with 440+6, P/S, P/B, A/C to the east coast and back pulling a trailer and had no problems. What you WILL find is at highway speeds, IF your outboards aren't pulled in, you will be running lean enough to make your exhaust manifolds glow bright red. This can be fixed by rejetting the center carb a bit fatter than stock. Might also back a bit of timing out of it.

But if your plans are to just cruise around in it on weekends etc, don't mess with them. If you don't know what you're doing, you're asking for trouble.
 
Do NOT mess with the idle adjustments on your outboards, especially on a "vintage" set of carbs. More often than not, they will be stuck and you will break off the ends of them trying to adjust them. And that isn't something that is easy to fix.....drilling one out, and trying to retap the passage.

Leave them alone. I've run them for years. Drove a 68 Satellite wagon with 440+6, P/S, P/B, A/C to the east coast and back pulling a trailer and had no problems. What you WILL find is at highway speeds, IF your outboards aren't pulled in, you will be running lean enough to make your exhaust manifolds glow bright red. This can be fixed by rejetting the center carb a bit fatter than stock. Might also back a bit of timing out of it.

But if your plans are to just cruise around in it on weekends etc, don't mess with them. If you don't know what you're doing, you're asking for trouble.


This is all true UNLESS you switch to the ProMax parts as I did on my car and would strongly recommend as it makes them very tuner friendly, especially if you have done cam, head, compression, stroker mods as I have. Unless of course you are an absolute numbers/parts correct freak. Of course I still have my original parts I took off in a box on the shelf.:)
 
You're right Darryl. There would come a point where it would be necessary to use something other than the O.E. type carbs. But if Don Little can run 10's with the O.E.'s, I figure they'll work for anything "I'll" ever be running:grin:
 
Have you checked to make sure the vacuum lines for the carbs are hooked up properly? Also, what cam are you running? Any idea of how much vacuum it's pulling at idle? There are also different springs for the vacuum pods like for a Holley 4V. Any idea what is in your carbs?

vacuum is poor yes because it's a big cam , but there are fresh holley rebuilt by holley, With i assume stock springs , do i need stiffer springs. The problem is i have weak vacuum already and with the secondarys opening up as soon as i hit the gas pedal ,that sucks off all my vaccuum. They should open up at speed when i need the other two carb right ?
 
Big cams and six packs don't mix well without a lot of work. You would need heavy springs to slow them down. If it were me, I'd ditch whatever you have in there in favor of a stock cam, or at least one of Bob's "blueprinted" cams. With sticky tires it's enough to take you to low 12's, and no problems with vacuum either.
 
Big cams and six packs don't mix well without a lot of work. You would need heavy springs to slow them down. If it were me, I'd ditch whatever you have in there in favor of a stock cam, or at least one of Bob's "blueprinted" cams. With sticky tires it's enough to take you to low 12's, and no problems with vacuum either.

i'm buying a vaccuum pump !
 
That will help with your brakes, but won't help with the carbs.

knock yourself out
 
I just took a look at the engine pics again. With manifolds you really shouldn't be running a stupid big cam anyway. Motor won't breath right. But as I said before...knock yourself out
 
How big is the cam? Is the timing in the tailpipe? What's the compression ratio? I'd say 220 deg @ 050" is plenty and 112 deg lobe separation. Hmmmm, factory magnum cam sounds about right.
 
Anytime you get into multiple carbs there are a lot of issues in itself. Then when you start modifing the engine from what the stock induction is set up for, it simply becomes trial and error with regards to tuning, jetting, etc. The best thing you can do is try to find someone that has the same mods you have and find out what did and more importantly, what did not work so you don't repeat the same mistakes.

I am still trying to sort mine out but have not really spent much time at it as with the fleet I have there is always someting else to work on. My six pack feels like the accelerator hangs up for a second or two at full throttle when you let off of it. However there is NOT anything hanging up. I believe it is something vaccum related but have not found it yet. Not a good feeling the first time it happened in 4 gear all out on the highway.
 
my super bird convert has a six pac motor the carb are newly remanned by holley

I am having vacuum problems ,( not stopping brakes?weak
we figured out the vacuum sec's are opening really quick and sucking off all my vaccuum on #1 and 3 carb .When at low start up speep when the center carb is all that shoud be working ? Any help ?


Have you checked the fitting at the power brake booster? I had this problem once on another car. The plastic had melted INSIDE that fitting and nearly closed the fitting completely off. It could not be seen from the outside.
 
Anytime you get into multiple carbs there are a lot of issues in itself. Then when you start modifing the engine from what the stock induction is set up for, it simply becomes trial and error with regards to tuning, jetting, etc. The best thing you can do is try to find someone that has the same mods you have and find out what did and more importantly, what did not work so you don't repeat the same mistakes.

I am still trying to sort mine out but have not really spent much time at it as with the fleet I have there is always someting else to work on. My six pack feels like the accelerator hangs up for a second or two at full throttle when you let off of it. However there is NOT anything hanging up. I believe it is something vaccum related but have not found it yet. Not a good feeling the first time it happened in 4 gear all out on the highway.

Do you have the safety linkage hooked up and/or adjusted properly? About 20 yrs ago my buddy had a six pac on his Charger (I have the set up now) and one "expert" decided to remove the mechanical override links that close the out board carbs on deceleration because he said it was preventing them from opening. We were 18 yrs old so what did we know. Anyway, a quick drive around the block taught us exactly why the linkage was there. Everything stuck wide open and the 4000+ lb car with 4 people in it got very greasy. The "older and wiser" test driver (after cutting the ignition) decided that the out board carbs were working just fine. With those big diaphragms I figure pretty close to 70 lbs of force to each carb at full vacuum.
 
One thing that can easily cause the "hanging" is the carbs (or A carb) being slightly off center. What happens is the throttle plates (usually on an outboard) will catch on a base to manifold gasket. I've seen this a bunch. So you might check for that. Drop your linkage and check each carb one at a time. Hopefully this will be the issue, cause it's the easiest thing to fix.
 
Couldn't make it through the novel above but did you check to see if the bleed hole in the center carb has been plugged or restricted on the outboard signal circuit?
 
Thanks for the suggestions on my hangin problem guys.

Yes, the safety linkage hooked up and seems to be adjusted properly.

I will check the other when I get back on this car. Right now my priority is to get my 1978 Little Red Express Truck being converted to 4X4 since I am now without a 4X4.
 
my super bird convert has a six pac motor the carb are newly remanned by holley

I am having vacuum problems ,( not stopping brakes?weak
we figured out the vacuum sec's are opening really quick and sucking off all my vaccuum on #1 and 3 carb .When at low start up speep when the center carb is all that shoud be working ? Any help ?

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Just stumbled across this 13 year old thread, I have an A12 Super Bee, I have been having "Issues" with linkage binding. Sometimes it's with engine HOT, or after sitting.. I open up CENTER carb to WOT, and outboards WON'T open without forcing one of the diphragm pods by hand, then all 3 work fine, for a while. Seems like now, (after reading all of this) could be a throttle shaft or bushing problem? The 2 4365 outboards are NEW Holley's, but by now Im sure most know Holley now is JUNK. Center 4144-1 is the ORIGINAL carb to the car..
Could be a misaligned baseplate, as I DID install a "SIX PACK PERFORMANCE" plate on rear carb that has ANGLED 45° Idle/Air screws..
Could be THAT baseplate.
Once I get the 2 end carbs Un-stuck, it runs killer... But? After it sits, there's that damnned "Binding Up" again.
Always something with 6 Packs...
 
6bbls do not have a posative stop for the outboard throttle blades, so they can stick..There was a problem with 1969 carb throttle blades1970 used a different blade to solve it. The fix was to sand the throttle blade edges so they no longer stuck to the bore, or 1970 blades. There was a tech tip in the old dc bible about this.
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