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  #1  
Old 02-16-2011, 02:08 AM
jeffz jeffz is offline
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Question help choosing carburetor

I have a 440 with alum. heads, MP sixpack spec. cam, MP alum. intake man. , flattop pistons, stock valvetrain, and the stock 1973 elect. dist. This is a fresh rebuild, never run since the '66 D100 it's going in isn't done yet. I'll be running a torqueflite with a stock converter, or trying to.
I've been doing some research, but still need help choosing:
Demon or Holley?
Mech. or Vac. secondaries?
Annular boosters?
Manual choke? The truck came with a choke cable, and I won't be dealing with much cold weather starting here in AZ.
Thanks in advance
Jeff (Newbie)
PS: I can post the cam specs if necessary. I'd share pics, but I don't have enough posts yet.
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  #2  
Old 02-16-2011, 10:22 AM
340_GTS 340_GTS is offline
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Holley 750 Vacuum Secondary with an elctric choke would be my choice. Sounds like a fairly mild combination, and with a low stall speed converter automatic, and a pretty heavy vehicle, the mechanical secondaries just won't work.
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Old 02-16-2011, 04:58 PM
John Kunkel John Kunkel is offline
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Are you interested in maximum performance or driveability? If you're more interested in driveability a smaller carb like a 625-650 will give better throttle response.
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  #4  
Old 02-17-2011, 12:08 AM
cudabob496 cudabob496 is offline
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Can't see a 440 with anything less than a 750, especially if the alum heads are good flowing.

Need info like cam spec, type of intake manifold, size of exhaust, headers, etc.

Holleys are usually preferred over Demons.
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  #5  
Old 02-17-2011, 12:44 AM
jeffz jeffz is offline
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Thanks for the replies. I'll dig up those specs and post tomorrow.
I know Holleys are more common than Demons, and the last all Mopar car show I went to, most of the cars had Edelbrocks on them. I see a Demon with elec. choke, vac. secondaries, 750cfm, and billet metering blocks for $419, but a Holley built the same way is over $50 more. Doesn't seem to be a clear consensus out there.
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  #6  
Old 02-17-2011, 08:39 AM
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JVMopar JVMopar is offline
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I personally like the Thermoquad. Is a good balance of economy and performance.

http://www.thermoquads.com/
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Old 02-17-2011, 02:33 PM
rampage_82 rampage_82 is offline
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I would also suggest a Vacuum Secondary Holley (or any of the derivatives I.E Proform, Quickfuel, BG, etc.) I would want it to be a 4150 style (same money better tuning)... I actually run a couple of Proform's and am having real good luck with them. I have run a bunch of AFB / Edelbrocks, and if they are on a real mild engine they do fine, but unfortunately I don't build very many mild engines and they are a pain (for me) if you have a lot of camshaft duration, which won't be an issue from what you described.
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  #8  
Old 02-17-2011, 06:16 PM
crisser crisser is offline
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I would run the 750, 3310, for a vacumn sec. carb. or the 700, 4778, if you want to go mech. sec.

Or try here.

http://www.holley.com/applications/C...bSelection.asp
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  #9  
Old 02-17-2011, 07:43 PM
rampage_82 rampage_82 is offline
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Also another tip if you go with a double pumper is to get one with 4 corner idle circuits, that helps tuning a lot...
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  #10  
Old 02-18-2011, 04:30 PM
jeffz jeffz is offline
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Cam: Dur. 228/241, Lift 450/458, 115 Lobe sep.
Manifold: Mopar Perf. (DCC-5153525 @ Summit) dual plane

Thanks for the suggestions. Holley's website was good, more helpful for choosing than BG.
What's the deal with a "ford kickdown". Can you use a ford kickdown on a Mopar? Pardon my ignorance. I'm trying to re-use the OE pivot and rod type throttle, and converting to AT with a torkflite, and the big, long kickdown rod that came with the RV engine/trans that I rebuilt.
I guess I'll have to check with the tech line before I order.
Thanks again, guys.
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Old 02-18-2011, 04:50 PM
rampage_82 rampage_82 is offline
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Ok that intake is basically a copy of an Edelbrock RPM with a Mopar Logo stamped on it... Your cam is barely above a stock cam, such as to the point you might not even be able to tell the difference, I know I have one in my Ramcharger. The specs on that cam are extremely deceiving and the actual numbers at .050" are actually closer to 208/221, and with the 115 Degree Lobe Separation it's very tame and mild. I dislike mine, however I think I really messed up when I slapped it together, and just put it in straight up, instead of degreeing it... LOL it doesn't make power anywhere...
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  #12  
Old 02-18-2011, 05:04 PM
340_GTS 340_GTS is offline
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All you need is a small Mopar adapter that bolts to the (almost) universal "Ford" lever that comes on 99% of all Holley street 4-bbls these days. Holley p/n is 20-7. http://www.holley.com/20-7.asp Your Mopar throttle cable and trannie kickdown mate up to this. Just make sure you have a stock stud/nut (where the cable hooks onto it). It does not come with the adapter.
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  #13  
Old 02-18-2011, 05:32 PM
John Kunkel John Kunkel is offline
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The OP states a 6-pack spec cam which is no different in timing than the 440-4 Magnum and the flat top pistons with aluminum head might actually yield less compression than a stock Magnum whose original carb was in the 650 range.
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  #14  
Old 02-20-2011, 03:49 AM
mhenesian mhenesian is offline
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Hi jeffz,

Best carb for your combo (IMHO) is the Edelbrock 800 cfm AVS carb $400 with electric choke (http://www.summitracing.com/parts/EDL-1813/). Anything less than a 750 cfm carb on a 440 is too small, whether it's a Holley or not. I would stay away from 600 and 750/780 cfm Holley's with vacuum secondaries. You'll be playing with secondary springs until the "cows come home". Also all Holley's require metering block, fuel bowl gasket, fuel inlet needle and seat, and power valve changing every two years or so. Since we race with Holley DP's from Proform and Quickfuel, we do this maintance at least one a year.

I ran the 440 magnum cam (268/284 deg 0.450/0.458" lift, same as your's) for many years with the original Carter 750 AVS carb on both Edelbrock Performer and Torker II manifolds and it pulled very hard to 5600 RPM with Hemi springs in the heads. You can make more power with this cam by retarding it 4 crank degrees. But in your truck I'd just install it straight up.

Today, Edelbrock has specific tuning kits (step up rods, springs and jets) that will help you get the 800 AVS really dialed in. You can do almost all the tuning without removing the top of the carb, just change rods and springs. Get it dialed in once and run it for many years with only periodic external cleaning with a few shots of carb cleaner,

Mark
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  #15  
Old 02-20-2011, 04:23 AM
340_GTS 340_GTS is offline
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I'm glad you said IMHO Mark. I've put 750 or 780 vacuum secondary Holleys on 383, 440, and 340 engines (all mild street/strip engines) for 30 years or so and never had to fiddle with any of the components you mention. They have run great out of the box. What is the reason for a full rebuild every couple of years? I've just never experienced the kind of problems you seem to have.
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  #16  
Old 02-20-2011, 12:27 PM
crisser crisser is offline
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Speaking of carbs, looks like Barry Grant/Demon carbs. are history.

From Barry Grant
As of today, February 18, 2011 we are ceasing operations at our Dahlonega location and all subsidiary locations. Working with all of you has been the experience of a lifetime. I will value your support as friends, customers, vendors, and media contacts forever. The economic situation has put the company in the position of not being able to find working capital needed to continue operations and get a chapter 11 reorganization plan through the court. In addition to this, is that all of our equipment has been breaking down causing production delays and further hurting cash flow. Reluctantly now we must convert to chapter 7 liquidation after 26 years of business. The financial collapse has closed, or has caused severe restructuring of many companies in our industry. Many individuals have lost everything. We have even lost our home. This is the most humbling experience of my life, and I have no future plans at this point. Thank You for Your Many Years of Support.
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  #17  
Old 02-20-2011, 03:17 PM
340_GTS 340_GTS is offline
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cry2

That sucks. Here is the article: http://www.dragillustrated.com/2011/...ll-operations/
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  #18  
Old 02-21-2011, 02:40 PM
jeffz jeffz is offline
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Well, I guess BG made my decision for me. Sorry for his employees.
FWIW, my cam was installed straight up.
Thanks again.
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  #19  
Old 02-24-2011, 04:15 AM
mhenesian mhenesian is offline
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Hi 340 GTS,

I guess I was spoiled by the hard running Carter 750 AVS carb that I put on my '69 383 Roadrunner. You could feel the engine pull a lot harder when the secondaries were opened. I could never quite get that same feeling with any vacuum secondary Holley. The first Holley I owned was a classic 3310 (780 cfm) version that came on the 1968 375 HP 396 CID Corvette, bought used in '73 (bought the carb, not the car !). Even with 3.55 gears and an 11" hemi converter, that carb would bog, unless I put in the brown or black springs, and then I could never tell if the secondaries were opening. Just not my kind of carb, sorry,

Mark
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Old 02-24-2011, 03:26 PM
John Kunkel John Kunkel is offline
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The vacuum secondary Holleys are self-regulating, the secondaries won't always open fully if the airflow isn't needed.

Even though the Carter secondaries open mechanically the airflow is also regulated by the airdoor.
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  #21  
Old 02-24-2011, 03:38 PM
cudabob496 cudabob496 is offline
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A nice 750 DP Holley is the way to go, if you like to mash the throttle, and take off with no delays.
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  #22  
Old 02-24-2011, 08:38 PM
dodger1 dodger1 is offline
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Quote:
Originally Posted by cudabob496 View Post
A nice 750 DP Holley is the way to go, if you like to mash the throttle, and take off with no delays.
That's exactly how my TQ works - stand on it right from idle and away we go. No bogs, no hesitation, and you'll know when the secondary airdoor opens. (TQ secondary throttles are mechanical, as are all Edelbrock/Carters, the airdoor is the key) Mind you I have a mild 360, not a built RB, but I've heard TQ's are quite adequate on most streetable engines.
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