Problem with a new 6 PACK

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scastillo

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Just a few moments ago, a friend call me to mention that he finished the installation of a new Six Pack setup that he bought in Year One for his 72 Duster 340, when he start the engine, in idle, the exhaust manifolds came very hot near to red color, and when he pull the gas pedal the outboard carbs dont want to open,,,he said that he connect all the vacum lines as the instrucction and some pictures form books and internet. I will go tomorrow to see what happen,,but if some pass this experience before I need your advice. Maybe is a litlle thing but I dont know. The car have a purple cam 274/ 480 and has Power Breaks, I dont know if this conflict with the vacum of the enginer or something. The owner mention to me that with his OEM Thermoquad run greats.

Advice are welcome.
 
also the end carb will not open just by pulling the gas pedal...they open went the engine is under load by the vacuum cannister on the end carbs...

they do not have mechanical linkage...they end carbs are just like vacumm controlled secondaries on a holley carb...
 
70aarcuda said:
also the end carb will not open just by pulling the gas pedal...they open went the engine is under load by the vacuum cannister on the end carbs...

they do not have mechanical linkage...they end carbs are just like vacumm controlled secondaries on a holley carb...
Click to expand...

Oh yes I know that, any way they dont want to open,,maybe the vacums dont want to work...
 
there is still linkage that connectes them to the center carb...that needs to be adjusted correctly.....

try and unhook the linkage...and see if they open....

actually while the engie is running the vacum is holding them shut...went the vacum drops...the spring in the cannister opens them up...

try and open them by hand went the engine is shut off...
 
70aarcuda said:
there is still linkage that connectes them to the center carb...that needs to be adjusted correctly.....

try and unhook the linkage...and see if they open....

actually while the engie is running the vacum is holding them shut...went the vacum drops...the spring in the cannister opens them up...

try and open them by hand went the engine is shut off...
Click to expand...

Nice Info,,,I will let you know tomorrow, i will work with it..
 
Hmmm, not sure that is right. I thought they worked just like a vac secondary holley 4 barrel. Which is the SPRING holds them shut, Untill vacume over comes the spring tension, thuss opening up. The linkage part pulls them shut when you let off the throttle. And also six pack setups are calibrated pretty lean, the probally need be richend up some, especially with the engine having a cam.
 
yeah...it might the other way...but with the engine off...it should open...

something is binding them otherwise....
 
To check to see if those end carbs are opening place a small clip on the vacuum pull linkage (nothing too tight...just want it to clamp lightly) against the vacuum pod on the end carbs and go for a ride. After a full throttle pull shut it off and check to see if the clips slide down the pull linkage away from the vacuum pod. This is the easiest way to see if they are opening under load.

I've made a few posts recently on 6 Bbl. tips. Do a search under my screen name and you'll find it. Too much to type this early w/o my coffee....
 
I have a 440 Six Pack in my 69 Barracuda. Trust me, when they open up, you know it. Holley does sell spring kits that allow you to dial in the opening rate of the secondaries. Chances are, you have very stiff springs that slow the opening more than you want. Of course, you will need two spring kits so that you keep the same spring. I would also recommend applying vacuum to each diaphram to make sure you don't have a bad diaphram. Since the two carbs are connected by a common vacuum line, one bad diaphram will prevent both from opening. As far as the linkage, all it does is close the throttle plates. Adjusting the linkages is just a matter of adjusting the lengths so that they fit easily into the holes when the throttle plates are closed.
Hope that helps.
Rod
 
Not trying to hijack the thread, but have been thinking about a 6 pack setup for my 340 in my 69 barracuda, is it possible to do this without carving up a hood?
Thanks
Steve
 
Look at the photo gallery in my signature above, the one under `68 Barracuda. I have a six barrel on my car and it fits just fine.... 8)
 
you probably need to take a look and see which colored spring in the diaphrams...

mine had purple springs if i remember ....
 
there is a trick to those springs and third hand to put the screws in is a big help. it took me two evenings and half of a saturday to tune mine and like the man said wen there right you will know because you will not hook it with basic street tires and hang on to it because you wont know witch way shes headed.I hated my 6pack wen i got it because it was all wrong.don't give up on it wen its write there is nothing that sounds like it.. Sum day I will have another.
 
I fix the problem!!

I found that the guy put the vacum lines in the wrong tube, he placed the vacum in the distribuitor tube, I open the needles a half in outboard carbs, and adjust the linkage a little bit, I start the engine,,,wow sounds good!! now is runnning excellent.!

Thanks for all advice and information!!
 
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