Six pack power valve....

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OK Experts. @brian6pac
I once again need some input from you guys.
I have a six pack on my car and like most, I said most, NOT ALL these six packs are a pain lol my question is.
Will it hurt my car, make no difference or help me...
If I swap the 6.5. pv to a 3.5 pv because I was told the reason the car does not idle properly, ( it used to before we played with it and all of a sudden it doesn't) is because the cam takes a lot of the vacuum (cam is 540 lift mechanical cam)
I don't know what to do with that issue now.
Thanks.
 
Wont help the idle, you need to put a vacuum gauge on it with a long hose and tape it to the windshield or have it on the dash where you can see it driving down the road. When you stand on the gas part throttle then full throttle and see how far the vacuum drops. A 6.5 wont open till the vacuum is below 6.5"hg and you will have to drive it to see. A Idle problem is probably a vacuum leak, what do you have at a idle for vacuum.
 
When the carb is correctly adjusted, the vac rating of the PV has NO effect on idle rpm or quality.
However, with a low vac cam like you have, the engine requires a higher idle speed & more air at idle. To fix this [ incorrectly ], folks often screw in the idle speed screw for the reqd air. Now the pri t/blades are open too far & fuel is being pulled from the main system. Fuel will be pulled from the main jets AND the PV if the PV vac rating is lower than the idle vacuum. This is the stinky, rich idle you often hear about. The correct fix is to add idle air by drilling the t/blades; the blades can then be reset to their correct position.
 
The PV has zero effect on idle. It's not on the idle circuit.
 
My 70 440-6 RR had an idle solenoid, that dropped the carb closed when the key was off.

Things that help to worsen "dieseling" or "after run" are too high idle, too LEAN idle, vacuum leaks, retarded timing, and running way too hot... With a bigger cam, getting the throttle blade too far out of the transfer slots can be a problem. First thing to try is see if it "likes" more advanced initial timing
 
The outboard carbs do have air fuel mixture screws that are preset and hidden behind lead plugs at the base of the throttle plates.
 
The end carbs do have something to do with idle, and each end is different. Do you have Promax baseplates? I have them on both ends, I did them on the front too, didn't like having my hands by the fan. An infared heat gun can be helpful too. Get your ctr carb jet size correct, idle, before moving on to wot. If you can not get your idle down with the ctr carb, one of the end carbs is too rich, and holding your idle up.
Play with it. I still haven't gotten mine completely right, but I am working on it!
 
I would start from scratch . Pull the carbs and reset the blades to expose the correct amount of idle circuit ( square) then readjust your idle timing for idle rpm. Vacuum advance disconnected ... then attach vacuum gauge and adjust idle circuit for highest reading . Then drive the car with gauge attached and readable as suggested for correct power valve selection .
Remember Six Pacs are nothing more than a four barrell with 2 secondaries.
 
thanks guys...
i know this sounds childish and fool proof but dont you know just when they invent knew childproof....anything, they just invent knew fools lol
i have aman now really was the grand master of hotrods in my city, hopefully he will solve and with everyone throwing in some ideas that seem like greek to me are written in a language he can decipher,,,
Once again,
thank you ALL !
 
I would say the six pack is a two barrel with four secondaries.
 
In my opinion the six pack is a labor of love and almost a constant learning curve. When everything is working correctly it's pretty Hardy but definitely more complex than a single four barrel set up I've been working with mine for about 5 years now and feel I have it dialed in pretty darn good but in my opinion to idle will always be the trickiest part.
 
I have heard the phrase, It's just a four barrell carb. Well, for me, there's a little more to it than that. It's like having ten connections vs two, more possibility for something to go wrong. They are 3 separate individual carbs and they all can effect the tune. Three times the trouble.
 
MOPARDY,


"Welcome to Chrysler's version of Jeopardy."

Your Host
Abody Cudas

"Today's categories are...
Hemi, Multi Carb and Max Wedge.
For 1 million headaches and a lifetime of deductions.

They are 3 separate individual carbs and they all can effect the tune. Three times the trouble."

""What is a SixPack "
DING DING DING.....WE HAVE A WINNER.

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