Who runs a six pack 340?

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71Duster

71Duster

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Well working out the bugs on my Duster and it's bog issues. Borrowed a 750 double pumper Mighty Demon, it was set up for a 408 stroker so it was pretty rich on my 340 but even so it ran better and the mid range and top end was way better then my 650 Speed Demon.

The bog was a little better but certainly no worse. Talked to a few guys at the engine shop and most opinions from the builders point to the cam not being degreed right or just needing to be changed in order to sort the off the line lack of power.

So while contemplating more carb for the car a 6 pack has always had a way cool factor to it also for all my carb issues been thinking about EFI. Does anyone here run a 6 pack on a 340 and what kind of an engine build does it take to make it work?

Any real issues tuning it?
 
340s have always seemed to like more carburetion than what they were born with. One of the early mods for the 68/69 340s was to put a 440 carb on. I run a big block with a six pack and I find it to be a nice way of getting the available carburetion you may need while still maintaining a lot of streetability and relative economy. Ha, did I say economy? :D
 
750 Holley vacuum secondary carbs have seemed to work well with mild 340s.

Also, Carter T-Quads can be very good, as these have small primaries, and huge secondaries.

Also, have you thought about the Holley 670 Avenger? A buddy of mine has one on his 360 Dart Sport and it works well, out the box, with a Comp Cams XE 268, headers, RPM Air Gap and Mopar ignition.
 
I run one and have ben since 2006. I love it. Iam running a stroked 340/6pac with 4 sp. It just feels GREAT when it come on. As for tunning it, My buddy and I set them up when I put them on. Never touched them since.
 
71Duster said:
Well working out the bugs on my Duster and it's bog issues. Borrowed a 750 double pumper Mighty Demon, it was set up for a 408 stroker so it was pretty rich on my 340 but even so it ran better and the mid range and top end was way better then my 650 Speed Demon.

The bog was a little better but certainly no worse. Talked to a few guys at the engine shop and most opinions from the builders point to the cam not being degreed right or just needing to be changed in order to sort the off the line lack of power.

So while contemplating more carb for the car a 6 pack has always had a way cool factor to it also for all my carb issues been thinking about EFI. Does anyone here run a 6 pack on a 340 and what kind of an engine build does it take to make it work?

Any real issues tuning it?
Click to expand...

Can you be a little more specific about the bog?

Is it on the initial hit ....or is it went the outside carbs open? Have you checked the acelerator pump on the center carb?

What spring do you have in the outside carbs? Are they stock carbs ?

Does it have stock linkage or has it been rigged to be mechanical...?
 
Sorry you misunderstood me, I don't have a 6 pack just a 650 speed Demon but I tried a 750 Mighty Demon and the mid range and top end where awesome.

The bog with my 650 is when I first hit it, did it with both carbs and with numerous tuning sessions.
 
check acelerator pump....soon as throttle is moved..pump needs to squirt gas...

also you might need to change size of squirter....
 
I have a 6pk on my 340. Runs well and gets 15mpg's on the highway. My engine is pretty much a stock 72 build. Low compression, mild cam and built for street driving and pump gas. It won't blow your doors off, but that wasn't the purpose of the build this time around......Been there, done that :wink:
 
I run the demon 6-pack carb's easy to tune.Fixing to change intake to the mod man with changeable top's.
 

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Hey guys im just getting into the older mopars and have a 72 demon my uncle and i are going to street build and was wondering what carbs to use with the 6 pack set up.
 
I put a 650 AVS Edlebrock on my 71 340,with a 484 lift cam,headers,Air Gap manifold. Tuned out of the box and it starts great(No Choke) Runs Great (No Bog,No hesitation) Top end seems to be good also but i am not drag racing it. Over All very happy with the combination. I think quite often we assume bigger is better...not always so with cams and carbs.
 
Jason65 said:
I put a 650 AVS Edlebrock on my 71 340,with a 484 lift cam,headers,Air Gap manifold. Tuned out of the box and it starts great(No Choke) Runs Great (No Bog,No hesitation) Top end seems to be good also but i am not drag racing it. Over All very happy with the combination. I think quite often we assume bigger is better...not always so with cams and carbs.
Click to expand...

alright cool i guess i will put up some stuff when we get the motor in...supposedly we also got a race cam..i got a buddy who can spec it out for me
 
jacksdodges said:
I run one and have ben since 2006. I love it. Iam running a stroked 340/6pac with 4 sp. It just feels GREAT when it come on. As for tunning it, My buddy and I set them up when I put them on. Never touched them since.
Click to expand...

You must have the Six Pack God on your shoulder.
Bless you my child if you can send some blessings this way.... Lol
Maps
 
6pk2goDemon said:
I have a 6pk on my 340. Runs well and gets 15mpg's on the highway. My engine is pretty much a stock 72 build. Low compression, mild cam and built for street driving and pump gas. It won't blow your doors off, but that wasn't the purpose of the build this time around......Been there, done that :wink:
Click to expand...

I love to read these types of posts, it gives me hope that one day I'll finally find someone who knows how to tune these... Until then, I cry, I cry alone.
Zoi
 
Me too. I am almost in disbelief that I just put them on and it ran fine right out of the box. I have changed things so many times I could scream. I believe that there are countless variables to making them happy, I just haven't found the correct road.
 
CRUZE 418 said:
Me too. I am almost in disbelief that I just put them on and it ran fine right out of the box. I have changed things so many times I could scream. I believe that there are countless variables to making them happy, I just haven't found the correct road.
Click to expand...

CRUZE 418

I gave up on the "road" Hell, even with a GPS and NASA at the controls can still get you lost.
I've come to realize that I must enjoy the path I'm going as the scenery can (and will) change abruptly on me. Like the weather, Never know what to expect..... Even with all sixpackologists telling how great tomorrow will be, I take it slowly....

It's like living in Florida and the morning (Radio) man says "Good morning friends, it's Sunny today and the high will 84 degrees here today in Northern Florida, we don't have a cloud in the sky .... Will be like this for the next 72 hrs...."
Meanwhile the guy living just down the shore is shaking his head while slowly take a sip from his morning cup of coffee while looking out the window at the rain coming down in buckets and the palm trees swinging from left to right from all the wind.
Thinking any minute he will hear time to get the windows (and everything else that's loose and about) nailed shut and down.
Welcome to Six Pack Ville.

Although when (weather) all is sunny....there is no better place to be....at, behind or with.
Just are you willing to travel to the 4th dimension, known as the Twilight zone?
MAPS
 
I have a 408 Six Pack in a 72 Dart. Does that count?

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Love it love it more. Love it forever...
The only thing I don't "like" are the exhaust manifolds.
Need to see some BIG LONG HEADERS (1 3/4, 2 INCH)
This doesn't mean I don't still love her, just would dress her with some taller spiked set of heels and lose the sneakers...

BTW. What kind of T stat is that ?
 
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