Six pack setup

[Nitrofish1]

Just out of curiosity, the 440 6 pack intake and carbs flow pretty well, but up to what engine size using a 440 block stroker setup would require you to swap out this setup in favor of a single or dual plane setup to maintain the correct F/A ratio, or would up to certain CI's become too lean? Or would you just swap in upped jetting on the six pack?

 

[440beep]

The Edelbrock Six Pack intake is a dual plane manifold. Mopar Muscle did a Six Pack 541hp stroker article recently and I think it was a 465ci motor; they up'd the main jets to 66 from the stock 64, and drilled out the secondary metering plates to 0.089. They also changed the power valve but didn't bother saying what they changed it to.

Just out of curiosity, the 440 6 pack intake and carbs flow pretty well, but up to what engine size using a 440 block stroker setup would require you to swap out this setup in favor of a single or dual plane setup to maintain the correct F/A ratio, or would up to certain CI's become too lean? Or would you just swap in upped jetting on the six pack?

 

[Nitrofish1]

The Edelbrock Six Pack intake is a dual plane manifold. Mopar Muscle did a Six Pack 541hp stroker article recently and I think it was a 465ci motor; they up'd the main jets to 66 from the stock 64, and drilled out the secondary metering plates to 0.089. They also changed the power valve but didn't bother saying what they changed it to.

usually at about 500 ci and above though they go with a dominator or dual 750's or something for more horsepower but if youre building for torque then id still want the six pack, but i wasnt sure if the six pack would just run out of steam at a certain point and not be able to support the engines F/A needs, possibly at the higher rev range.

 

[lewtot184]

if i understand your question correctly; basically it's not a fuel flow/jetting issue thru the carbs but at what point does the manifold become a restriction. for maximum power the manifold needs to flow more air than the heads. fuel flow thru the carbs can be anything you want, extreme rich or too lean or just right.

 

[440beep]

Considering the Six Pack's three carbs are rated at 1350 cfm I don't know how you'd run out of fuel unless you have them so not dialed in, or the fuel pump sucks and the carbs are starving for fuel at the top end which is a valid concern. What's a dominator? 1050?

This is something I will be dealing with shortly and hoping my Hemi fuel pump will be enough for the CIs. I followed the Mopar Muscle article and up'd the main jets to #66s, have a 6.5 power valve in, and drilled the metering plates to 0.089 so hopefully I'm close for the fueling needs. May have to play with the secondary diaphragm springs to tune in more/less fuel as the vacuum disappears.


As for the air needs, my car friend mentioned the same thing to me last night. I have a 2" new/improved stock Six Pack air filter, and I also have a 3" K&N oval air filter I can put on; so my friend's like "you better put that 3" filter back on becuae that motor's gonna need all the air it can get," even though I hate the look of the 3" filter and incorrect Six Pack base.

 

[rumblefish360]

The six pack flows well for what it is. The 1350 CFM rating is at the 2bbl. rating which equals some where around just under 950 CFM as a 4bbl. rated carb. I forget the exact conversion number. What does your engine require?

The next item in the A&F path is the intake manifold as perviously mentioned. The statement is correct! The intake needs to flow better than the heads. I have read before that the 6 pack intake can flow up around 300cfm when lightly ported.
If your heads out flow the intake, a change is in order for maximizing performance.

Taking it to the max is something you will have to decide. It's not a must but a bennifit to do so. And only you will know.

Lastly, the engine itself! Cubic inch aside, what the engine will need in terms of A&F to feed it is a engine combo related issue no matter the size of the engine. After all, you could build a low rpm 500 or a big rpm 400 that both will use or out strip the manifolds ability. It is the engines demand for air and at what rpm you expect to be turning it at.

A 500 will consume more, quicker at a lower rpm than a 400 otherwise equally built. Even though the intake has a 2500-6500 operating rpm range, you could use it up earlier in a 500 or just simply run out of intake manifold with a high winding 400.

Also mentioned above, with bigger hp engines, the move to a single plane and carb becomes the "What's needed" for that application. If your going to bud the 6 pack regulardless, you may have to back down on aggressive cam timing and reduce the expect Hp output level for a well balanced and running engine, which would be a lot better and nicer to drive than a over cammed pig that can breath where it count and is wanted most.

MoPar used to have a "Tip" section where the 6 pack is used to run in the 11's.
Is this E.T. good for you?

 

[Nitrofish1]

The six pack flows well for what it is. The 1350 CFM rating is at the 2bbl. rating which equals some where around just under 950 CFM as a 4bbl. rated carb. I forget the exact conversion number. What does your engine require?



MoPar used to have a "Tip" section where the 6 pack is used to run in the 11's.
Is this E.T. good for you?

Yes lol. The more research I do the more my engine size keeps going down so that I would be able to use the six pack setup. Yes, I could throw a Dominator on a single plane and make a strip beast, but as my friend the other day asked me, "is this car for racing or for tooling around town?", and the answer is the latter. I'd like the motor to be more powerful than a plain 440, and therefore I'm gonna be making a stroker but the bigger it is the more i'd have to mess with it.... im sure i could easily make it an 11 second car running between 450-500ci, but as far as using a six pack on something like a 540 or 572 isnt happening with this car.

 

[wedge69]

I ran the super stock intake and LOVED IT ! But was a PRO STREET set up for sure !
My 440 was pumping out big #'s but the thing would flat out fly !
Tuned rite when those other two kick in it's like another shot in the *** !

 

[Meep-Meep]

I ran the super stock intake and LOVED IT ! But was a PRO STREET set up for sure !
My 440 was pumping out big #'s but the thing would flat out fly !
Tuned rite when those other two kick in it's like another shot in the *** !View attachment 164318

Did you do the recommended mods in the intake? Looks good!

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One thing that hasn't been mentioned is the 6 BBL intake is a divided plenum dual plane type and that also makes a difference. The totally divided plenum is what keeps the stock engine from falling on its face with all those carbs by providing a stronger signal to the venturi. One can simply cut most of the divider out between the two holes and possibly improve the entire RPM range but that would be highly experimental and can possibly ruin the intake. The above Weiand tunnel should do the job very well but is a fuel distribution nightmare. Same goes for the Edelbrock STR.

 

[wedge69]

Yes I did. I weldid aluminum bars in it at the points specified and flow ported the upper side of the base. I had Very good help from a long time racer in York PA who ran super stock for years !
To be honest the thing had good street manners for being a 13.1 motor !!
But it did Shell out a 9" ford rear on me ! Pulled the Pinion rite out the front ! NEVER had any other car do that before !!
And I buld rear's for them all.

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Also on your note about the cut the plennume deal. All you need to do is mill a slot (passige) between the two ports at the carb base to equel out the signal. This slot will Balince out the cylinder feed and not hurt the low end pull.
We had a motor on a circle track car that would pop off the turns . It was fuel stravasion to one or more cylinders. We put and open spacer on the intake inplace of the 4 hole and it was all good !

 

[Nitrofish1]

Horsepower TV did a nice 451" motor out of a 400 block with a six pack, some mild Eddy heads and mild cam, got 480hp and 550tq, not too shabby. Was looking at the Muscle Motors 383 to 496" short block, that'd do nicely for my Coronet. Otherwise the 440 to 511" short block would be another good choice I was thinking. Alot of the out of the box Eddy heads flow either 210cc or 280-290cc on the intake ports, wouldn't be going too crazy with some 350cc port job motor....

I could easily do up to 525" or so on a stroker block but I really wanted to use the six pack... and retain some reliability by keeping the power in check.

 

[rumblefish360]

You could so a 500-512 like cube motor and use the 6 pack well. Your RPM range would be lowered a little bit. Selecting a cam with the RPM range to 6500 would be the ideal match for the RPM range of the intake as well as the street. Shift a few RPM's above it. With the added 60 cubes, it'll be a great street ride!

Go with a cam lift that tKes advantage of the heads flow ability. Use a rosr rocker for the best advantage of a true 1.5 or 1.6 ratio and less friction. It will make a mean street machine.

 

[Nitrofish1]

You could so a 500-512 like cube motor and use the 6 pack well. Your RPM range would be lowered a little bit. Selecting a cam with the RPM range to 6500 would be the ideal match for the RPM range of the intake as well as the street. Shift a few RPM's above it. With the added 60 cubes, it'll be a great street ride!

Go with a cam lift that tKes advantage of the heads flow ability. Use a rosr rocker for the best advantage of a true 1.5 or 1.6 ratio and less friction. It will make a mean street machine.

 

[440beep]

Great information!!!!!

For those who've messed with a Six Pack on a 500ci motor, any tips on tuning the carb setups?

 

[rumblefish360]

See the set up as a 4bbl. With extra secondaries. Set the outboard idle screws, tune the center as well as possible then go to your secondary side. What you do to the front you do to the rear.

 

[Nitrofish1]

See the set up as a 4bbl. With extra secondaries. Set the outboard idle screws, tune the center as well as possible then go to your secondary side. What you do to the front you do to the rear.

i could keep it a sleeper with the 383 -> 496 six pack, however it wouldnt have the cold air application to keep it discrete, might cut the power down,

 

[rumblefish360]

The cold air app. will not slow it down. It will just keep cool air coming in, not hot air. This means it stays edifice when running. No power loss from hot air.
I don't know about the power difference between the single 4 and the 6er, a lot depends on what intake and carb are used.

 

[Nitrofish1]

The cold air app. will not slow it down. It will just keep cool air coming in, not hot air. This means it stays edifice when running. No power loss from hot air.
I don't know about the power difference between the single 4 and the 6er, a lot depends on what intake and carb are used.

i got the six pack hood scoop as part of the car, and im sure if i didnt use it it would stare me in the face the rest of my life....

 

[ord27]

I can't contribute much to the math on this subject, but...
back in 2001 i had a '71 Cuda 440 six pack. I found a local guy in Grand Prairie to help me build it. He raced old chevys.
we bored it 30 over and put in pop up pistons to increase the compression. I think we were running just over 11:1.
intake, carbs, heads were all stock, but polished. I can't remember how big the cam was, but the car had a nice lope.
He told me that we were around 500 hp at the tires. I don't know if that's accurate. I do know that the car was a beast. It would accelerate from 60 to 120 incredibly fast. 120 to 150 really strong! I never tried to get it any faster.
That's also running the stock four speed. I can only imagine how fast and quick it would be with a tremec in it!!

I don't recommend driving them that fast, but my point is, there is plenty of power in a 6 pack setup. The down side was having to run super, plus an off road octane boost. If not, it wouldn't run well

 

[wedge69]

Man I LOVE that 6 pack scoop ! It just Screams NASTY !!