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Why the six pack ?

I wonder if it was just to be different. They did seem to run well when tuned right. A primary carburetor in the center of the intake sure equals better fuel distribution than the dual four barrel Hemi setup did.
I do find it interesting that a single 850 cfm 4 barrel can walk away from a 6 pack setup.
 
More than likely to keep up with the competitors. Or bring them back. It wasn't a new thing.

Pontiac had the three twos back in the 50s, TriPower.
Ford used them.
Chevrolet used them.
The 50s Hot Rods souped their flat heads up with aftermarket setups.
 
Cause holley was making them for the corvette, so they were available. If there were no carbs, there'd be no sixpack. (Three dueces holleys date back to 67 on corvette 427s)
 
The dual fours on the Hemi were not very streetable. Whereas, running a center 2-bbl with another 4-bbl secondary made a much better overall street-friendly performance combo. And, no 4-bbl ever walked away from me back in the day.
 
Yet the 69 sixpacks automatically came with a 4.10 gear, no choice. Hardly an economical cruise gear.
I wonder about that. I have a Super track pack V code Challenger that I’ve owned over 10 years, and the times I’ve taken it on highway runs to car shows, I’ve been surprised how little gas it uses. On the other hand, I also have a 383 Challenger with a 3:23 rear and it seems to guzzle gas on the highway.
The V code is a pain on the highway due to running 3600 -4000 rpm doing 60-65 while all the maniacs on the road pass me. But it seems somewhat good on gas for some reason.
In my youth I remember an article in Car Craft by Al Kirshenbaum where they had stuck a 440 6 pack in a mid 60s B body, Fury maybe, and being the mid 70s with gas shortages and all he mentioned they were pleasantly surprised by that builds mileage.
I was a member of the T/A AAR SIAC and in the early 80s guys would boast in the newsletter about getting 17-18 mpg on road trips from their 340 6 Packs.
So maybe there is something to the economy of running on just a 2 barrel down the highway.
I’ve also heard it said a 440 6 pack with 4:10s at 60 mph is just loafing!
 
More than likely to keep up with the competitors. Or bring them back. It wasn't a new thing.

Pontiac had the three twos back in the 50s, TriPower.
Ford used them.
Chevrolet used them.
The 50s Hot Rods souped their flat heads up with aftermarket setups.
You forgot Olds and Cadillac.
 
It's basically a 2 barrel system with 4 more "vacuum secondary" barrels.

Not real easy to do that with two 4 barrels.

Pretty well thought out IMO.
 
If the engines a match & only difference is the intake
I'll take the 6bbl on the street over a single 4bbl or 2x4bbls
especially on a low profile 2x4bbl inline set up, until you start spinning over
6,500 RPM & WOT all the time, like dedicated drag racing
if that is the case I'd go with a tunnel ram & 2 big 660-750cfm 4bbls
or a single 4bbl fro a dominator carb & 1050+ cfm Dominator carb for all out racing

6bbl/Six-Pac 'actual cfm flow' is 940cfm,
about the perfect amount for a mild modified 440,
especially with headers free flowing exhaust
or a lil' hotter 383/400, it will spin more
(6bb=1350cfm if it's all added up 350+500+500, 'but doesn't flow close to that stock')
driving around on a 2300 Holley 2bbl 350cfm does make it a bit economical
(mine, the center 350cfm inboard carb flow 415+cfm, with a few minor mods,
still retained the choke-horn, butterfly/shaft screws & knife ground throttle plates
)
but that temptation of hearing the 2) 500cfm secondaries/outboards come in is priceless
& it had/or still has great curb appeal

for the posers at the car show

todays sh-t gas doesn't help, a single 4bbl makes for less hassles
I need to replace the 3 needles & seats, on the 6bbl
more often if it sits for much/any time
I run an electric fuel pump after I'm done driving it I turn the pump off
& let it run to get 'most the fuel out', of the bowl so it doesn't leave
as much crappy gas residue for all the freaken' additives today
I currently go about 3-4 years on needles & seats it seem,
I'm not driving a crapload daily either, so it sits 5+ days a week

but;
at least it's not a freaken' shitty OE Carter 4bbl
or Webber/Edelbrock knock off
now maybe a Competition series Carter AFB, then it'd be a bit better

The 6bbl it has it's down falls from the factory,
harder to change jets, restrictive 5/16" fuel lines from the factory
PITA to remove & service
The rear & front/Outboard 500cfm vacuum carbs, don't have replaceable jets,
they have jet plates, fixed bores/orifices (you can drill them but then your stuck)
easy fix ProMaxx or Quickfuel etc. (or others) make adj. screw in style jet plates
for the outboard carbs
but for a stock engine, the org. plates they are pretty damn good out of the box
if you get the right carbs

I've run a crapload of (Plymouth) 6bbls (Dodge six-pack)

the factory 6bbl/Six Pack intake needs the center divider on/under the center carb spot
carved/notched down/out, knife ground/cleaned up some (Vanke Mod)
if you plan on modifying the engine under that intake
makes for a way better flowing intake charge
add a couple phenolic 1/2" to 1" spacers & about 3-4 jett sizes, will really wake it up
actually on the top end it helps too, more RPM if the valvetrain is set up for it

I've ran several different intakes Edelbrock STR14 440-6 was a great combo after the
needed mods, low end torque monster, not that great above 6,500rpm
but 440/RB were ever intended for above 6,500rpm (a 383 HP barely could)
stock style B/RB wedge heads are a huge choke point
went 10.90's on that 446cid STR14-6, fully dress 69 RR, street-racing monster in the later 80's
Budnicks 69 RR 440ci str-6bbl #2.JPG

OE cast iron MoPar wedge heads
(unless you port them &/or run MW heads, but then have to highly modify
the manifold intake ports & it kind of kills the purpose of the cross ram
long runners effect, for the intended low end torque, getting you
in a heavy car, off the line quickly
)

I had better luck with the low-deck STR15 (383-6/400-6) 4.15" stroker 479cid
still needed a bunch of lil' mods to make them work 100%
Edelbrock STR-14-6 Tom Hoover mods Direct Connections bulletin page 47.jpg



I have a MP 383-400 6bbl intake currently, slightly modified, ports worked
AN -6 line, 1" phenolic spacers & I like the results, wow my drivers rats nest :poke:
68 RR #29 479ci-6bbl #6 AN lines & phenolic spacers ps.JPG


both the STR-14 & 15 manifold in single dominator
or singe 1450 950cfm 3bbl square bore
perform absolutely great right out of the box, if you know how to tune a good carb,
like Holley, stager jet them after reading the plugs, make it right
(or todays Oxygen sensors & AFR gauges aides)
still the appeal of the 6bbl is worth giving up a lil' at after 6,200 - more like 6,500+
unless you are running at wide open all the time

same deal with the stock 6bbl intakes, I prefer the Alum. versions
weight savings/heat distribution alone is worth the change

a single 4bbl like a Edelbrock Performer RPM alum intake,
hands down best 'pure street intake'
(with a proper sized Holley vac. sec. if it's a Auto & DP if it's a 4 speed
CID x RPM div.by 3456 = CFM, more RPM more flow is needed/bigger carb/cfm
)
It's also a dual plane alum. manifold, it has the center divider trimmed out already too
will be way better on the street
(the 6bbl will make like 15-25 more HP, if the mods I described are performed at a lower RPM)
with a 750-950cfm carb, especially with a 1" 4 port tapered spacer under it
depending on what mods have been done to the pump/long block below the intake
(1/2" if you have hood clearance issues, used with a good drop base air-cleaner)
they work well, far better than any stock iron 4bbl intake & Carter/Edelbrock
Chrysler/Dodge/Plymouth never had an Alum version of a single 4bbl big block
That I can remember anyway...

Maybe go to a vintage Edelbrock Tarantula TM7 or TM6 single 4 bbl single plane intake
works great, they are easy to find on the -www- fits well under the hood of these cars too

as you can see I like the 6bbl/six-pack
but in reality it really depends on the build
people rarely build these cars for milage, most people go overboard anyway

opinions will vary vastly probably as many as there are posts
that's my educated experience, take it or leave it

I hope you enjoyed reading the book :lol:
 
Last edited:
If the engines a match & only difference is the intake
I'll take the 6bbl on the street over a single 4bbl or 2x4bbls
especially on a low profile 2x4bbl inline set up, until you start spinning over
6,500 RPM & WOT all the time, like dedicated drag racing
if that is the case I'd go with a tunnel ram & 2 big 660-750cfm 4bbls
or a single 4bbl fro a dominator carb & 1050+ cfm Dominator carb for all out racing

6bbl/Six-Pac 'actual cfm flow' is 940cfm,
about the perfect amount for a mild modified 440,
especially with headers free flowing exhaust
or a lil' hotter 383/400, it will spin more
(6bb=1350cfm if it's all added up 350+500+500, 'but doesn't flow close to that stock')
driving around on a 2300 Holley 2bbl 350cfm does make it a bit economical
but that temptation of hearing the 2) 500cfm secondaries/outboards come in is priceless
& it had/still has great curb appeal

for the posers at the car show

todays sh-t gas doesn't help, a single 4bbl makes for less hassles
I need to replace the 3 needles & seats, on the 6bbl
more often if it sits for much/any time
I run an electric fuel pump after I'm done driving it I turn the pump off
& let it run to get 'most the fuel out', of the bowl so it doesn't leave
as much crappy gas residue for all the freaken' additives today
I currently go about 3-4 years on needles & seats it seem,
I'm not driving a crapload daily either, so it sits 5+ days a week

but;
at least it's not a freaken' shitty OE Carter 4bbl
or Webber/Edelbrock knock off
now maybe a Competition series Carter AFB, then it'd be a bit better

The 6bbl it has it's down falls from the factory,
harder to change jets, restrictive 5/16" fuel lines from the factory
PITA to remove & service
The rear & front/Outboard 500cfm vacuum carbs, don't have replaceable jets,
they have jet plates, fixed bores/orifices (you can drill them but then your stuck)
easy fix ProMaxx or Quickfuel etc. (or others) make adj. screw in style jet plates
for the outboard carbs
but for a stock engine, the org. plates they are pretty damn good out of the box
if you get the right carbs

I've run a crapload of (Plymouth) 6bbls (Dodge six-pack)

the factory 6bbl/Six Pack intake needs the center divider on/under the center carb spot
carved/notched down/out, knife ground/cleaned up some (Venke Mod)
if you plan on modifying the engine under that intake
makes for a way better flowing intake charge
add a couple phenolic 1/2" to 1" spacers & about 3-4 jett sizes, will really wake it up
actually on the top end it helps too, more RPM if the valvetrain is set up for it

I've ran several different intakes Edelbrock STR14 440-6 was a great combo after the
needed mods, low end torque monster, not that great above 6,500rpm
but 440/RB were ever intended for above 6,500rpm (a 383 HP barely could)
stock style B/RB wedge heads are a huge choke point
went 10.90's on that 446cid STR14-6, fully dress 69 RR, street-racing monster in the later 80's
View attachment 1670232
OE cast iron MoPar wedge heads
(unless you port them &/or run MW heads, but then have to highly modify
the manifold intake ports & it kind of kills the purpose of the cross ram
long runners effect, for the intended low end torque, getting you
in a heavy car, off the line quickly
)

I had better luck with the low-deck STR15 (383-6/400-6) 4.15" stroker 479cid
still needed a bunch of lil' mods to make them work 100%
View attachment 1670233


I have a MP 383-400 6bbl intake currently, slightly modified, ports worked
AN -6 line, 1" phenolic spacers & I like the results, wow my drivers rats nest :poke:
View attachment 1670230

both the STR-14 & 15 manifold in single dominator
or singe 1450 950cfm 3bbl square bore
perform absolutely great right out of the box, if you know how to tune a good carb,
like Holley, stager jet them after reading the plugs, make it right
(or todays Oxygen sensors & gauges aides)
still the appeal of the 6bbl is worth giving up a lil' at after 6,200 - more like 6,500+
unless you are running at wide open all the time

same deal with the stock 6bbl intakes, I prefer the Alum. versions
weight savings/heat distribution alone is worth the change

a single 4bbl like a Edelbrock Performer RPM alum intake,
hands down best 'pure street intake'
(with a proper sized Holley vac. sec. if it's a Auto & DP if it's a 4 speed
CID x RPM div.by 3456 = CFM, more RPM more flow is needed/bigger carb/cfm
)
It's also a dual plane alum. manifold, it has the center divider trimmed out already too
will be way better on the street
(the 6bbl will make like 15-25 more HP, if the mods I described are performed at a lower RPM)
with a 750-950cfm carb, especially with a 1" 4 port tapered spacer under it
depending on what mods have been done to the pump/long block below the intake
(1/2" if you have hood clearance issues, used with a good drop base air-cleaner)
they work well, far better than any stock iron 4bbl intake & Carter/Edelbrock
Chrysler/Dodge/Plymouth never had an Alum version of a single 4bbl big block
That I can remember anyway...

Maybe go to a vintage Edelbrock Tarantula TM7 or TM6 single 4 bbl single plane intake
works great, they are easy to find on the -www- fits well under the hood of these cars too

as you can see I like the 6bbl/six-pack
but in reality it really depends on the build
people rarely build these cars for milage, most people go overboard anyway

opinions will vary vastly probably as many as there are posts
that's my educated experience, take it or leave it

I hope you enjoyed reading the book :lol:
Someone asked me who my favorite author is. I replied "Budnicks", his books are lengthy but well worth the read. :drinks:
 
I think " walk away" is a bit strong. Take a look at this https://www.motortrend.com/how-to/mopp-0212-six-pack-system-test/
You can read the results. I can tell you results. From personal experience, back in the day. I destroyed most takers, you had to have a stout combo to keep up. Of course I didn't run against the "race-ready" cars, but the usual street-strip cars... Chevy's were the most formidable opponents. I ran mechanical linkage with a fuel log fed by a Carter (the best) electric pump.
 
Remember that hemi guy Tom Hoover? Well back in the day he used to give seminars...he always spoke of how well a hemi would run on a six pak due to fuel distribution etc vs the 8bbl. Faster than the 8bbl according to Mr Hoover.
Anyways you all can pontificate all u want, a properly tuned six pak will out run it's 4bbl or 8bbl equivalent. Street cars not this race car crap. 5/16 fuel lines will support a lot of horsepower... Currently in the stable is a 505 alum head roller cammed A12 car that runs with hellcats...must be a mistake that six pak working so well with a mechanical fuel pump and those 5/16 fuel lines
650+ hp....
 
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