Now I know why six packs aren't on every big block.

[Rocket]

sheesh I am real close to being done with my six pack experiment. Rebuilt the carbs, put in AED Jet plates with 84 jets. took my time with them. Pre adjusted the middle carb to 1.5 turns and the outside carbs to 3/4 turns out. Installed them on the car. Got the fuel lines perfect.

Before I rebuilt the carbs I sent the dizzy to Don @ FBO and he put a vacuum can back on it and calibrated it to the vacuum my car puts out ( I think 13 at idle).

All that to say, I tried to start it today. Put the distributor in a place where I thought it would start. Yes it "started" but it wouldn't idle at all. it sounded very weak. I will pull the plugs and see if they are soaked like they have been before. I checked the wires and they are all going to the right cylinder. I moved the distributor a bit and when it backfired through the middle carb I was done. Probably messed up the power valve.

I thought this six pack would be fun....

 

[CompSyn]

Mr.6pack

Before you give up, I'd give Bob a call,



This is how a Six Pack should run:

[video=youtube;OFaPlDt2jt4]http://www.youtube.com/watch?v=OFaPlDt2jt4[/video]

 

[mahoney0_00_3]

yes they look cool and sound better they are neat,my buddy had a 440 six and I had a 440 and a 1000 cfm 3 barrel holley my holley run like a dream are engines were the same cam and headers in to glass packs the intake was taller off the block with the single carb but ran /going to put the same carb on my hemi/love they have the single four barrel for it now!/only way to get the carbs right is to use a multi-vac gauge/like for a cycle/runs off the center/out board are dumper carbs/any pre-set vac and look up carb vac-action and ck it on the stick and hand pump the vac to make sure the carb work and your car will run great hope that helps/your car should idle with no out board carbs

 

[pinkpanthr]

Sounds like you have the outboards operating when they should be closed. At idle and up to about half throttle you should be running solely on the center carb. Only when you really get on it should the secondaries get in on the action. I've never messed with a six barrel as far as tuning so I'm not sure if that would be a linkage adjustment or if its vacuum controlled or what. Whichever, thats where I'd start looking.

 

[Rocket]

Thanks guys. I called Bob and he was very helpful. I really appreciate that CompSyn. I am going to tough it out.

 

[ACME A12]

Rebuilt the carbs, put in AED Jet plates with 84 jets.

Two thoughts here:

1) Is this a typo? A 64 jet is usually what most guys run. Even the F.A.S.T. guys don't run more than a 65 or 66.

2) Since it won't idle and you've soaked the plugs before maybe go back to square one. Obviously you know to set the idle mixture screws on all three carbs to get the proper air/fuel mixture at idle. Even though the the outboards are only metering air at this point they are still part of the equation. There are several VERY knowledgeable guys over on the LOH Playground and they will tell you not to take the outboards more than 1/4 of a turn out from seated as they're very sensitive. You already have three times that. Might want to run those puppies back in...

Maybe Bob K already covered this with you. Not sure, so I thought I'd throw my :cents: in...

 

[mac]

I feel your pain. I went through a long period before things started to make sense.

 

[Rocket]

no typo the outside carbs would be in the low 80s. The middle carb is a 63 I believe.

 

[Rocket]

I asked Bob (great guy by the way) if just buying new carbs makes sense and he said it would. The carbs I am using are over 40 years old. Can i get them to work ? heck yeah we shall see.

 

[Big John]

Yea, 84 would be .099, about the size of the metering plate jet size.

Have you run this distributor before?? The vacuum reference is bothering me too.... 13 in/hg at idle?? Where do you have your distributor vacuum advance hooked to?

The manifold vacuum doesn't have much to do with your advance vacuum as the advance vacuum is taken at the carb venturi. As the air rushes by the hole in the venturi, the vacuum builds and advances your distributor. This is also the vacuum source that opens the end carbs. The manifold vacuum drops as you open the throttle.

You know..... 90% of carb problems are electrical.... just saying....

 

[mac]

I asked Bob (great guy by the way) if just buying new carbs makes sense and he said it would. The carbs I am using are over 40 years old. Can i get them to work ? heck yeah we shall see.

ended up with a new center carb and like magic everything fell into place. I tried to get the old carb to work and after changing metering plates and power valves and jets with nothing ever giving good results.

 

[Rocket]

John,
I had it set up by Don at FBO. I will have to recheck that vacuum #. He had me go to the manifold to check it I just assumed I'd go there when I ran it. Should I go to the carb?

Yea, 84 would be .099, about the size of the metering plate jet size.

Have you run this distributor before?? The vacuum reference is bothering me too.... 13 in/hg at idle?? Where do you have your distributor vacuum advance hooked to?

The manifold vacuum doesn't have much to do with your advance vacuum as the advance vacuum is taken at the carb venturi. As the air rushes by the hole in the venturi, the vacuum builds and advances your distributor. This is also the vacuum source that opens the end carbs. The manifold vacuum drops as you open the throttle.

You know..... 90% of carb problems are electrical.... just saying....

 

[Rocket]

Do you any of you six pack guys use the Carter 4845? http://www.summitracing.com/parts/crt-m4845/overview/
I have a 3/8" supply with a 1/4" return after the pump it goes down to 5/16 via a 5/16" nipple . Am I creating too much pressure by necking it down?

 

[Big John]

John,
I had it set up by Don at FBO. I will have to recheck that vacuum #. He had me go to the manifold to check it I just assumed I'd go there when I ran it. Should I go to the carb?

No, it doesn't go to the manifold. It goes to the distributor vacuum port on the right side of the carb.

This may explain your problem. The vacuum advance will be all over the place using manifold vacuum.

 

[pinkpanthr]

No, it doesn't go to the manifold. It goes to the distributor vacuum port on the right side of the carb.

This may explain your problem. The vacuum advance will be all over the place using manifold vacuum.

Sorry to hijack but do all Roadrunners use full vacuum advance? Or did any used timed advance?

 

[Big John]

Sorry to hijack but do all Roadrunners use full vacuum advance? Or did any used timed advance?

Full vacuum advance

 

[pinkpanthr]

Full vacuum advance

Thanks John

 

[Big John]

John,
I had it set up by Don at FBO. I will have to recheck that vacuum #. He had me go to the manifold to check it I just assumed I'd go there when I ran it. Should I go to the carb?

I just read the tech section at his site.

He was saying that cars with 10 in/hg or less shouldn't use vacuum advance. I assume he had you check your manifold vacuum to see if your car would work OK with vacuum advance.

 

[Rocket]

John,
That may be it! I think I have the vacuum and the outboard diaphragms switched too. What a dolt. Ok really dumb question ... a broke one of the sides off my idle adjustment on outboard carb. How do I get it out?

While all of this was happening with my car today I get a parking ticket for parking my van in front of my own house! Tomorrow will be a better day!

 

[zupanj]

What is FBO?