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Channing Spencer
06-21-2017, 09:27 PM
Does anyone know why the carb intake holes are linked on this Dual Quad manifold?

Thanks

Paul Steinberg
06-21-2017, 10:38 PM
I would guess that it is to balance the fuel delivery. What do the carburetors look like. When dealing with aftermarket parts, when you have a question like this, then it is best to ask the manufacturer what they had in mind.

John ED Renstrom
06-21-2017, 10:54 PM
Mix the file and air to keep from running raw gas into the cylinder. The problem with all this stuff is it's made for high RPM.

Channing Spencer
06-22-2017, 12:42 AM
Mix the file and air to keep from running raw gas into the cylinder. The problem with all this stuff is it's made for high RPM.

Good point about the high RPMs. It looks cool under the hood, but the 390 is not exactly a high revving engine. They were offered from the factory with dual quads though. I was wondering if it would wake up the engine a bit.

Channing Spencer
06-22-2017, 12:47 AM
I would guess that it is to balance the fuel delivery. What do the carburetors look like. When dealing with aftermarket parts, when you have a question like this, then it is best to ask the manufacturer what they had in mind.

I believe this intake is made for Carter Wcfb carbs. The manifold fits a Cadillac 390.

Kurt Arends
06-22-2017, 08:30 AM
I owned a '59 Cadillac Series 62 6-window sedan with a factory installed triple deuce set up in the early '80s. It would have been a factory option on anything other than the El Dorados. The triple deuce was only stock equipment on the '59/'60 El Dorados.

I am not aware of dual 4 bbls having been factory installed on any of the 390s('59 & after).

Paul Steinberg
06-22-2017, 08:47 AM
From my memory, they offered the 3 deuces in one year, and the dual quads the following year, and alternated back and forth. I don't believe that either was a popular option.

John ED Renstrom
06-22-2017, 11:27 AM
On has to remember how the 4 barrell carb works. It runs off the front two and the back opens up on demand. The cross pattern is what feeds each cylinder in Either mood. But on this one each carb only feeds 4 cylinders. That is the rubber. Keeping half the engine from running to lean or to rich. It makes for daily driving a problem. You fight it all the time driving it around town.

Peter Grave
06-22-2017, 05:44 PM
Folks the manifold is a Weiand (speed part) not GM. Two fours were on the Eldorodo in 55 and I think 56. Cadillac did the three two deal but dropped it in 61 due to service issues.

Paul Steinberg
06-22-2017, 09:28 PM
Folks the manifold is a Weiand (speed part) not GM. Two fours were on the Eldorodo in 55 and I think 56. Cadillac did the three two deal but dropped it in 61 due to service issues.

I believe this intake is made for Carter Wcfb carbs. The manifold fits a Cadillac 390.

No one ever said it was a GM part, and it is kind of difficult not to notice the name of the manufacturer in the middle of the manifold.

Peter Grave
06-22-2017, 09:38 PM
OK that was my point poorly made perhaps. The cut out benieth the carbs was a speed part design. The Cadillac and Packard two four manifolds did not have this. I suspect due to the fact it may roughen the idle up. Years ago I changed a couple of Packard Caribbeans from two fours to the single four barrel of the rest of the line because the owners did not like the rough idle and harder starting of the two four barrels.

John ED Renstrom
06-22-2017, 09:54 PM
one more of those either look cool or run decent choices. :rolleyes:

Paul Steinberg
06-22-2017, 10:36 PM
I remember setting one up, and the idle circuit was on the primary's on both carburetors, and each carburetor served only 4 cylinders. You had to work at getting them synchronized properly, and they ran smooth once you got that done. It was more of a "balancing" act than anything else. The linkages had to move smoothly and in exact synchronization. It could be done, but most people didn't have the patience to do all the adjustments exactly, and you had to have 2 carburetors that responded exactly alike when the secondary's opened up. Everything from float level to jetting had to be exactly alike.

Channing Spencer
06-23-2017, 12:05 AM
I guess looking cool will be running well with one carb... Thanks, you guys talked me out of it...saved me tons of money too...lol

Peter Grave
06-23-2017, 11:11 AM
HEY!!! Over 60 years ago I had a buddy who put three twos on his flat head Ford boy did it run bad. Plus fuel mileage went down to nothing (not good even if gas was 32 cents a gallon). He was heartbroken three chrome air cleaners it was beyond cool what to do? Being nuttsy kids we improvised removed the two end carbs and made from dog food cans block off plates to put between carbs and the manifold then I soldered the gas fittings to the two end carbs closed (no gas to carb now). Put it all back together and NEAT three cool carbs two of which were dummies but real cool at Hamburger drive in hangout.

John ED Renstrom
06-23-2017, 08:33 PM
My kind of three duces