B block 6 pack

[BSB67]

I had 440 carbs on my 383. Ran Great.

 

[Mopar Miki]

This is not drag racing! Street cars

Six pak will outrun the 4bbl on the same engine.
Always
The hit from the six pak is like no other - like having an NOS button that does not run out of gas.
This is not rocket science -there is some good documentation out there that requires brain engagement and some special tools.

 

[BSB67]

Six pak will outrun the 4bbl on the same engine.
Always

Without qualification, this statement is a bit misleading.

 

[33 IMP]

Without qualification, this statement is a bit misleading.

...and untrue.

 

[6PKRTSE]

Which carbs do you run on the 383 six pack?

The same part # 440 Auto carbs.

 

[Jerry Hall]

I've had no trouble, my 440-6 carbs were NOS from the 80's and work as designed. My 400 based 451 is just slightly more cu in than a 440, so not much additional tuning was needed. The 6bbl has much more kick when engaged. Also as designed, the speedometer goes right and the gas gauge left.

 

[6PKRTSE]

Just my personal comparison with running several of my buddies over the years (5) with big block 4 bbl B Bodies. (1) with a low deck stroker 451, the others with mild build 440's. My car gets them all by a 1/2 car to over a full car + each when playing on the street. And, my car is even several hundred pounds heavier than their cars being that mine is a loaded R/T S.E.
No, my car is not undefeated by any means. There is always someone faster.

 

[RemCharger]

 

[murfman]

I have 340, 383 short deck and 440 Six Pack set ups. All three have always performed well. Six Packs get a bad name due to most don't know how to tune them.

Exactly, when I bought my Superbird back in 87 the six pack was gone, and it had a TM7 and a 750 Holley carb on it. I was at a show and literally bought 6?pack setup from a guys trunk, he wasn’t even there for the show, just driving by. Long story short, I rebuilt the carbs myself, jetted them and drilled the outboard metering plates as per the old Direct Connection Bible installed them and played with the springs on the vacuum secondaries, am never touched the carbs again for 10 years, ran whatever pump gas I stopped at with an occasional tank of leaded 110 octane race gas and never had an issue with them.

 

[murfman]

Which carbs do you run on the 383 six pack?

Besides jetting the 340 and 440 carbs were the same. So it really doesn’t matter as long as you jet them and get the correct vacuum secondary springs in them.

 

[DeltaV]

Besides jetting the 340 and 440 carbs were the same. So it really doesn’t matter as long as you jet them and get the correct vacuum secondary springs in them.

Is the center carb different for 4 speed cars?

I already have the intake, but nothing else for the setup.

 

[murfman]

Is the center carb different for 4 speed cars?

Just jetting

 

[33 IMP]

Well there were different list numbers for every variation and year change.... but all basically the same, whether for 727 or 833. Jetting change here, a little distribution tab there.
And you can thank Chevrolet for the Sixpack carbs. If they weren't using the tripower holleys on the corvette, there wouldn't have been hotrod two barrel holleys to use.

 

[33 IMP]

Is the center carb different for 4 speed cars?

I already have the intake, but nothing else for the setup.

Chinese holley 4412s, $151 ea for three (ebay). Chop off the back of the aircleaner flange, get three side hung bowls and floats, progressive linkage..... and you'll have 1500 cfm (2bbl rating, closer to 1100 in real life) of air with accel pumps on all three, just like the progressive setup direct connection used to sell, many many years ago.
Cheapest way I've found to get new carbs, since the real things are about $1800, and the corvette carbs that holley used to sell cheap are LOOONNGGG gone!

 

[murfman]

Chinese holley 4412s, $151 ea for three (ebay). Chop off the back of the aircleaner flange, get three side hung bowls and floats, progressive linkage..... and you'll have 1500 cfm (2bbl rating, closer to 1100 in real life) of air with accel pumps on all three, just like the progressive setup direct connection used to sell, many many years ago.
Cheapest way I've found to get new carbs, since the real things are about $1800, and the corvette carbs that holley used to sell cheap are LOOONNGGG gone!

Only issue is if I go with carbs, I want the Vacuum secondaries

 

[33 IMP]

Only issue is if I go with carbs, I want the Vacuum secondaries

Nothing wrong with that!
But then you're stuck with finding a rebuildable set, or a huge bill for new ones (thankfully, they are still available, tho way,WAY overpriced)
You could also look for corvette carbs..... but they may not be ten cents cheaper than mopars.... and maybe more.