2 - quads vs sixpack on '67 440 hp

[66Satellite47]

Not sure that the tunnel ram makes much more power than a good 1 x 4 manifold combination.

 

[lewtot184]

a 2x4 tunnel ram is king in power potential.

 

[rumblefish360]

heres a NON Mopar comparison of 2 x 4 VS 3 duce.

that being said, the six pack looks kinda cool, works pretty good. but the CH 28 properly tuned should smoke a six pack.

Those carbs are all the same size IIRC. So it is down on cfm which equals power.
Check Holley's web site for actual cfm ratings.

If you raced, I'd say stick with the 850 dp (might even run a 750 vac sec if automatic). If you are looking for the cool factor & have hood clearance issues, I'd vote for a stock RB 2x4 intake with some mild port work and smaller carbs like 500cfm Carters

Good reply and probably the best & easiest bet.

Not sure that the tunnel ram makes much more power than a good 1 x 4 manifold combination.

This is not exactly true but mostly a combo dependent issue. Putting more carb on top of an engine that can't use it is t going to produce better results. An extreme example is a tunnel ram 2x4 on top of a stock engine. How does twin 500's do better than an engine that can't even use the full breathing available from a TQ?

As said earlier, ultimate power is found in a tunnel ram. Best used when used for its intended RPM range & purpose.

I myself would like to try out a dual plane dual quad.

 

[66Satellite47]

I ran Weiand tunnel rams on my 440 & 452 low deck motors with 650 DP Holley's. Got the shooter size & shooter cams figured out, jetting only a couple numbers larger than stock, with power valve plugged and front jets matching rear. Worked great. Very consistent. About 1 1/2 - 2 MPH & .05 faster than my TM6 or TM7 with 850 DP.

 

[62 Dart Convertible]

A dual quad runs around on 4 barrels.

On crossrams and inline dual quad without progressive linkage - yes.

On inline set ups with a progressive linkage - no. Light throttle cruising is on 2 barrels only.

 

[RAWPWR]

I like the way dual quads look on my 440.

 

[doc332]

I never see any 440s with 2 quads on the. At least not on a 67 Plymouth Satellite. Why not? Does that not make a descent set up? Or is the 6 pack better. I'm running a 850 pro Holley right now,915 heads ported polished , headers 3" exhaust, digital ignition, 373 rear end. Am I crazy to thin that 2 - 4s would be the ticket, or, do I go with the 6 pack or stay with the po Holley.What brands and models in the intake and carbs? I could look for advise on the internet, but experience always wins out over paper tests.

I like to keep in mind that all multiple carb setups date back to a time when there weren't any LARGE single 4bbl carbs to choose from. If your main concern is to look cool and run multiples, you will also need to accept the fact that manifolds, air cleaners, and carb/throttle linkages all cost money as well. There is also the ever present issue of keeping MORE THAB ONE carb in tune as well as synchronized. It is more than most of us can do to keep ONE CARB in tune. So the added expense of chasing that tuneup over time needs to be added in as well. There are charts, computer formulas and more to throw all your hard parts in and figure out how many CFM you should need. One carb will do if it is properly selected.

 

[khryslerkid]

I like to keep in mind that all multiple carb setups date back to a time when there weren't any LARGE single 4bbl carbs to choose from. If your main concern is to look cool and run multiples, you will also need to accept the fact that manifolds, air cleaners, and carb/throttle linkages all cost money as well. There is also the ever present issue of keeping MORE THAB ONE carb in tune as well as synchronized. It is more than most of us can do to keep ONE CARB in tune. So the added expense of chasing that tuneup over time needs to be added in as well. There are charts, computer formulas and more to throw all your hard parts in and figure out how many CFM you should need. One carb will do if it is properly selected.

But that wouldn't be any fun. We are talking Mopars aren't we?

 

[BCBOUND]

....ok thats it. I'm officially looking to buy a CH 28 2x4 intake for my 440...

 

[Cava3r4]

if you are driving it on the street, I'd stick with a single four barrel. 3 deuces would be better then the dual quad unless you got a big tunnel ram.
I had a 440/500 cube stroker motor built that had edlelbrock heads, intake, single 800 thunder series edelbrock (basically a new carter AVS) with a Lunati voodoo cam. It was actually running rich. I should have went with the 750. Don't forget, an original 440 magnum had a 635 Carter AVS on it!!
ran the quarter mile at 11.73 at 113 with 3.23 gears and my automatic. Just put it in drive and stomp on it. WORKED great.
I'm sorry that I sold the car. IT went to HOLLAND. everybody on this site told me it was worth nothing because it was F-5 Medium Green Metallic, Green Vinyl Roof, Green leather interior. I got 47K for it.
It was originally a 383-4v matching numbers S/E car. I sold the matching numbers motor with it. The guy in Holland sold it for 69000 Euros (about 73K US dollars).
Did that in Jan of 2017.

 

[lewtot184]

quads are not a tuning headache. you'll have more issues with some big jive *** single holley than a pair of AFB's.

 

[lewtot184]

this is pair of 600's, 1406 and 1405. i had these laying around for years and didn't use them until about 3 yrs ago. i was a die hard 6pak guy and still like them until i got into these quads. these things start and run nicely; very smooth power. plugs burn scary clean. mpg is better than the 6pak. i changed everything i could think of on these carbs to "make them better". they' re real close to the way they came out of the box now. if i were to do it again i'd buy 650 avs's. the 650's will be very close to ideal jetting as they come out of the box. if i had a stroker i'd do 750's. and before the commet begins; there's absolutely no such thing as "too much cfm". a carb can't make one cfm least wise too many. these carbs have velocity controlled secondaries and there's no reason to "over carb". you'll have more issues trying to straighten out one big 4bbl holley than these two afb's. and, these fit under the hood.

 

[doc332]

quads are not a tuning headache. you'll have more issues with some big jive *** single holley than a pair of AFB's.

I agree. But there are plenty of Holley guys who would tell us we are full of .... I have owned and driven reliably 2 street hemis in the 80's and 90's with zero complaints. Have had 2 hemi race cars, an altered and a RED, with iron blocks and inline Carters, with no complaints. Both motors were mild, with the same cam, an old Racer Brown solid roller with only .561 lift and 309 duration (advertised), always started easily and ran great. No big jive *** Holleys for this guy either. I think the earlier thread with the 800 Thunder Series is right on. It would be way too easy to over carb a street engine. The most accurate way to verify proper A/F ratios is on a roller with a sniffer, and a tuner who knows what he is doing and can make the necessary changes on the spot. For a few hundred dollars you can come out smelling like a rose, with no guesswork involved.

 

[68 HEMI GTS]

I know the single 4 vs the six pack is always a hot topic. Pretty dead heat on my street car. I think the six pack is just as fast.

Tm6 -1050an

Six barrel

 

[sawdust]

Here is a different setup. An old Weiand P3690982 modified for dual 4 carbs. If all goes well I will run it this weekend at Cecil, have to see what it runs. 440 11:1 Probe race pistons, ported Edelbrock RPM heads, Comp XTQ294 solid mech cam. Hemi 4 speed with 4.10 Dana. I'm guessing low 11, maybe high 10 if it hooks.

 

[wstrowig]

I never see any 440s with 2 quads on the. At least not on a 67 Plymouth Satellite. Why not? Does that not make a descent set up? Or is the 6 pack better. I'm running a 850 pro Holley right now,915 heads ported polished , headers 3" exhaust, digital ignition, 373 rear end. Am I crazy to thin that 2 - 4s would be the ticket, or, do I go with the 6 pack or stay with the po Holley.What brands and models in the intake and carbs? I could look for advise on the internet, but experience always wins out over paper tests.

I ran my 67 440 (DC-292/509) set up with a 6-pack, then the 750afb (4327S) re-jetted and metered on a TM7 manifold. The 6-pack turned a lot of heads but the performance went to the single carb. I often thought about the possibility of running dual 4s (i.e.. 2x750afbs)???

 

[sawdust]

I ran my 67 440 (DC-292/509) set up with a 6-pack, then the 750afb (4327S) re-jetted and metered on a TM7 manifold. The 6-pack turned a lot of heads but the performance went to the single carb. I often thought about the possibility of running dual 4s (i.e.. 2x750afbs)???

That's what I have , dual 750 Edelbrock 1407. Running a air/fuel gauge to get them right, the need some pretty rich jetting with the intake to get things metered properly.

 

[wyrmrider]

question about cc on 915 heads on previous page
opening up around the valves you end up with around 80 cc depending on stock or os valves and how much milling
74cc is blueprint minimum for super stock but they are larger than that stock

 

[66Satellite47]

Not sure what you mean by "opening around the valves". I took one set of my 915's down to 65cc. Thin intake rail, but worked pretty good.

 

[wyrmrider]

just scribing the chamber to the size of the bore and removing iron where the intake flows into the chamber
DO NOT OPEN TO THE GASKET
you can do it by hand or get started with your valve grinder- I have access to a Serdi which cuts down on the work
you can also chamfer the top of the block (useless on the exhaust unless you have an interference problem like big valves on a 413)
but helps flow on the intake. you have to mark where the top of ring travel is as you do not want to relieve there !!!
pretend- visualize that you are gas flow coming in the intake and past an opening and open valve- what's in your way
darn- the chamber is bigger than the block bore and the gas hits that ledge
btw a 6-71 makes the best dual quad manifold otherwise just for looks but work well with afb/ avs holly is a PITA