Sixpack question

[salinasjoel]

Hey just doing some research for my next potential build and had some questions?
1. Are the sb and bb six pack carbs the same?

2. I can only find the oem setup of one center 350cfm and two outboard 500cfm is that what would have been on the 340?

3. With the vacuum setup as apposed to other progressive carb mechanisms do you still get the fuel economy at low ends and the power at high end and is it easily adjustable? Or do they make a progressive setup for the mopar Holley six pack?

Thanks for all your help, I have a general sense of how it is all setup just looking for experience and details.

 

[moper]

1. The center carb is unique to each engine. I personally think that's mostly for basic jetting and power valve deals, but technically they have different part numbers.

If you want a six pac, unless you have personally ridden in the car that had the one you're selling, buy new. Stay away from factory originals because I've found the majority have issues created by people trying to "tune" them or just plain wear and tear. Just my personal opinion...

2. The centers are all 350. All outboards are 500cfm. That is correct for 340s.

3. You get much better economy with the vacuum, and when tuned properly, and working properly, you get very similar performance between the two. I prefer the vacuum on any car not racing 100% of the time. The linkage is progressive normally, I know guys that have made them all operate together, but IMO the cars were turds this way until the engine speed got high enough to really use all that cfm. Also, in terms of apples to apples comparison, the six pac when flowed with fuel (wet) is only about 1000cfm. HP Holleys, Dominstors, and custom shop carbs, and BG/Demons are all flowed wet.

I'll also add, if top HP numbers are your goal, the six pac on small blocks is not a great intake. On an enggine making 450+, the six pac will give up 40hp even when tuned perfectly over an Air Gap and single 4bbl.

 

[salinasjoel]

1. The center carb is unique to each engine. I personally think that's mostly for basic jetting and power valve deals, but technically they have different part numbers.

If you want a six pac, unless you have personally ridden in the car that had the one you're selling, buy new. Stay away from factory originals because I've found the majority have issues created by people trying to "tune" them or just plain wear and tear. Just my personal opinion...

2. The centers are all 350. All outboards are 500cfm. That is correct for 340s.

3. You get much better economy with the vacuum, and when tuned properly, and working properly, you get very similar performance between the two. I prefer the vacuum on any car not racing 100% of the time. The linkage is progressive normally, I know guys that have made them all operate together, but IMO the cars were turds this way until the engine speed got high enough to really use all that cfm. Also, in terms of apples to apples comparison, the six pac when flowed with fuel (wet) is only about 1000cfm. HP Holleys, Dominstors, and custom shop carbs, and BG/Demons are all flowed wet.

I'll also add, if top HP numbers are your goal, the six pac on small blocks is not a great intake. On an enggine making 450+, the six pac will give up 40hp even when tuned perfectly over an Air Gap and single 4bbl.

Thank you for the info, this is exactly what I wanted to hear. I think I will go with the six pack as I am looking for balance between power and economy. Plus it looks cool when you pop the hood.

 

[demon seed]

I would agree with Moper, I've driven both 340's and 440 six paks and if you're looking for the wow factor then they are certainly that. Personally I can get a good 4 barrel and manifold engine to run quicker that the 6 pak mostly cuss the single 4's easier to tune. I've also experimented with dual 4's and I won't do that again mostly cuss tunings a ***** and ya gotto have an engine that can handle that sudden inrush otherwise she'll fall flat on her face.

 

[moper]

They are the best in terms of eye candy. People just sit and stare. I drove one for two years, all year long, including in the snow. They are just awesome for a street car, but you should be up on carb tuning to get them set up.

 

[Ma Snart]

Thanks for the info guys. Everything said here is what I have heard before:

1 - Buy New

2 - More power from a good 4 barrel/intake set up

3 - Nothing cooler than a six pack

I am planning to go six pack on my 71 Charger

Ma Snart

 

[1970Duster]

Thanks for the info guys. Everything said here is what I have heard before:

1 - Buy New

2 - More power from a good 4 barrel/intake set up

3 - Nothing cooler than a six pack

I am planning to go six pack on my 71 Charger

Ma Snart

Not quite, there is nothing cooler then an EFI six pack!! Do a quick search on here you'll find a member has that EFI setup.

 

[DUSTPAN340]

That would be me that has the EFI set....NOW IT IS COOOOL,,,LOL and i had a six pack complete for sale not long ago...then i went six pack EFI...there is nothing cooler then that...stock does not compare....just my opion....

but yes...buy new if you can find one....OR PM ME ABOUT EFI...

CLICK ON MY View Photos By: DUSTPAN340 there are some pics of it there...i have more to load

 

[70aarcuda]

6 pacs are eye candy...better performance and fuel mileage from a 4 barrel with a better intake manifold...

and i have driven a 340 6 pac....

 

[Ma Snart]

70aarCuda

You are right , but I have trouble controling my eye's sweet tooth. LOL!

Nice Cudas in your gallery. Do you race the 2nd gen? My 67 pic attached.

Ma Snart

 

[Mopar to ya]

My brother has collected carbs, intakes, air cleaners, etc for the 440 in his 66 Charger. He rebuilt all the carbs and has spent 6 months with the owner of The Carb Shop trying to get all the proper linkages. I think his troubles are only beginning. It's enough trouble tuning a single carb, but three? I have to admit though, there is not much cooler looking under the hood than a six pack, and when someone asks what you have under the hood it is cool to see their eyes light up when you say "a 440 6 pack!"

 

[DUSTPAN340]

can you say EYE CANDY the new tech way......:blob:

 

[Ma Snart]

Sweet!!!

Looking forward to WW to see it in person

Ma Snart

 

[DUSTPAN340]

SHE'S RUNNING...turned the key...fired right up....

 

[Bulldozer]

man that is an absolutely awesome set-up with the WOW factor all over the place.im lovin it for sure.cant wait to get my paws on one of them....

 

[Ma Snart]

Glad to hear your car is puring again - See ya at the WW

 

[rklein383]

I don't think tuning a 6-pak is hard at all... if the carbs are in good shape. It's no different than any other Holley. I have an original 69 6-pak that I wrestled with for a while, until I replaced all three throttle plate bases. This got rid of the vacuum leaks by the shafts and allowed me to adjust air fuel mixture screws. Yes, the outboard carbs do have air/fuel mixture screws. Once I did that, it was easy. A vacuum operated 6-pac is really just a vacuum operated 4-barrel, just happens to have the extra secondaries separated from the main carb.