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Offenhauser dual carb setup for the flathead six

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  • Fuel System: Offenhauser dual carb setup for the flathead six

    I purchased an Offenhauser dual carb intake and linkage some years ago and finally got to install it - or at least I am trying to. I have installed two We 2417S carbs and am trying to fit the Offenhauser dual throttle linkage. I have tried every which way to fit the linkage but nothing seems close at all. The instructions are a bit quirky and I'm wondering if I got a Chinese copy! The photos I have found of the Offy linkage package for the 170 & 185 flatheads w/ WE carbs seems to be what I have???
    Has anyone been able to install the Offy linkage?
    I would like to see a photo of the linkage set up on a running flathead.
    I have attached the instruction sheets. The instruction "Attach stock throttle rod to tubing furnished with the Tee at rear carburetor." makes absolutely no sense!
    The diagram shows the 'T' linkage as being offset. Mine is not and so tends to his the fuel bowl of the rear carb - when set up one way. When turned over the T arm to connect with the throttle linkage hits the intake manifold.
    Too bad Bill C. isn't still in business. I'm sure I would have gotten the correct linkage package from him!
    Need help if I'm going to be ready for the driving season out here in Nova Scotia.
    gg
    Attached Files
    www.kgworks.ca/studeparts

  • #2
    Have you tried Googling Studebaker Champion dual carburetor? Try this: https://www.google.com/search?q=Stud...pr=1.2#imgrc=_
    Last edited by 52-fan; 01-21-2017, 06:26 PM.
    "In the heart of Arkansas."
    Searcy, Arkansas
    1952 Commander 2 door. Really fine 259.
    1952 2R pickup

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    • #3
      Originally posted by 52-fan View Post
      Have you tried Googling Studebaker Champion dual carburetor? Try this: https://www.google.com/search?q=Stud...pr=1.2#imgrc=_
      Thank you for the tip.
      I have gone quite deep into google but, so far no luck in finding a photo or description for the installation of an Offy dual carb linkage on a 185 with two 2417 carbs. The kit instructions says that it fits '39-'54 Champion models. I assumed that since the 185 was basically the same dimensions as the 170 and that the '57 WE carbs were also basically the same outside as the '54 models that the Offy manifold and linkage should fit. The manifold fits fine and the carbs fit the manifold fine.
      Still lost and expecting to have to build my only linkage.
      gg
      www.kgworks.ca/studeparts

      Comment


      • #4
        Originally posted by kg.works View Post
        Thank you for the tip.
        I have gone quite deep into google but, so far no luck in finding a photo or description for the installation of an Offy dual carb linkage on a 185 with two 2417 carbs. The kit instructions says that it fits '39-'54 Champion models. I assumed that since the 185 was basically the same dimensions as the 170 and that the '57 WE carbs were also basically the same outside as the '54 models that the Offy manifold and linkage should fit. The manifold fits fine and the carbs fit the manifold fine.
        Still lost and expecting to have to build my only linkage.
        gg
        Try posting a picture of what you got with the "kit" for linkage-maybe it's missing something that others will recognize.

        Comment


        • #5
          Originally posted by karterfred88 View Post
          Try posting a picture of what you got with the "kit" for linkage-maybe it's missing something that others will recognize.
          OK
          Here's some shots of the kit including a temporary install.
          The kit shown is missing the four carb studs and a couple of nuts and bolts to secure the linkage to the carbs.
          The shot with the linkage bottoming out on the intake is where it sits so that both carb throttles are closed. In this shot the linkage is also close to or in contact with the rear carb at the base.
          The second shot is with the linkage flipped. With the throttle partly open the linkage is blocked by the rear carb float bowl.
          If the linkage arm was off set that would solve that problem. Another problem with the linkage in that position is the linkage doesn't allow the throttles to close unless the linkage arm is so high the throttle rod would push it up instead of down.
          Attached Files
          www.kgworks.ca/studeparts

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          • #6
            Originally posted by karterfred88 View Post
            Try posting a picture of what you got with the "kit" for linkage-maybe it's missing something that others will recognize.
            Messed up the post.
            Here's the photos.
            Attached Files
            www.kgworks.ca/studeparts

            Comment


            • #7
              There is something off in the design I think. the linkage crossbar should be mounted in bearings securing the point of rotation and the darn linkage arms would be connected to this assembly with short arms that are adjustable for proper synchronization between the carbs. The whole idea is to open both throttle plates at exactly the same moment in rotation. The linkage needs to be fully adjustable for just that reason so they can idle and accelerate evenly. Look at linkages that are sold aftermarket for VW bugs with dual carbs, they should work the same. The actuator linkage should be adjustable as well so the idle is done by adjustment on the carb and not throttle pedal position. I worked with German cars doing tune up work for many years so I am familiar with the function of the linkages. I ran Webbers on my cars for years. Are these the only pictures you can find for the application?

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              • #9
                Click image for larger version

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ID:	1712161Since there are no "swivels" installed on the shaft, and no mention in the instructions. I would assume the carb arms of the rod assembly, would be situated 180 and backwards, and bolted "solid: to the carbs at the place where you are attempting to use a swivel. Then the tightly bolted assembly would rotate together and open both carbs simultaneously, the only adjustment would be at the connecting bolts to the throttle arm. In essence one solid rotating mass operated by moving the long center arm with the throttle rod from the car. Poorly designed but could work--arms on assembly lining up and overlapping with the arms on carb, using the carb throttle shafts as the axis. I can draw it but can't describe it any better. Take the "swivel" bolts out, turn the shaft so that its behind the carbs, align the outer arms over the carb arms and secure with bolt and tighten. moving the long arm would then rotate both carb butterflies at the same time, even if it moved the connecting rod somewhat up and down. In other words it floats with the only attachment the carb throttle arms bolted tight.
                Last edited by karterfred88; 01-22-2017, 09:50 PM.

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                • #10
                  Mine was working well, or so it seemed, when I got the car. I have no idea if the linkage was modified from the "kit" or whatever source it came from. My guess is it was installed a long time ago. The video gives you a quick glimpse of how it worked. I only drove it a few times before removing the engine.

                  1948 48 Studebaker Champion Starlight Coupe - Test Drive to demonstrate engine and transmission w/ overdrive. 169 cubic inch flathead straight six cylinder ...
                  Trying to build a 48 Studebaker for the 21st century.
                  See more of my projects at stilettoman.info

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                  • #11
                    The diagram in the second picture of your first post shows it correctly. The text about the tees and tubing is confusingly written. There is a line, with tees, to provide manifold heat to the chokes, and another for fuel. Distributor vacuum comes off only the front carb, I think. Referring to the fourth photo in your second post, I think the carb coupler rod (for lack of a better term) is positioned incorrectly. You need to swap ends. You will note the middle arm is not centered on the shaft. The "long half" of the shaft should be to the rear, and the "short half" to the front, with the middle arm sticking up. The end arms are to be bolted securely to the throttle linkage arms of the carbs, such that when the middle arm is moved to the left, both throttles open. The middle arm should then couple nicely to the factory throttle linkage coming across the middle of the head. You will need a fairly soft throttle return spring on EACH carb, because if the coupler rod ever comes loose, you want the "disconnected" carb to drop to idle, not go wide open.

                    Try fitting it up that way, and see if that helps.

                    This style of throttle linkage does not make it easy to balance the two carbs. Assuming that reversing the coupler rod as described above gets it in the ballpark, I would approach balancing the carbs as follows. You are going to need a Unisyn carb balancer. A British sports car shop ought to have one you might borrow.
                    1. Initial setup, engine not running, back off both idle speed screws until throttle plate is fully closed in carb bore, then advance both screws until their tips JUST touch the pad on the throttle arms of the carbs. Bolt your coupler rod in place securely to each carb and hook up the linkage. (I am assuming here that all fuel and vacuum lines are done, and that throttle setup is the last remaining chore.)
                    2. Turn each idle speed screw in one full turn. Hopefully, that will give you enough idle throttle opening for it to idle, once warmed up.
                    3. Start the engine, and let it run until it is fully warmed up, and the automatic chokes have fully opened, so that the fast idle cams are not in play. If it won't idle, tweak each idle screw up by equal amounts for each carb, until it will idle steadily. (with a solid linkage like this, ONE idle screw will hold both throttle butterflies open, but you don't want to rely on that)
                    4. Loosen the screw holding the coupler rod to the rear carb.
                    5. Place the Unisyn on the front carb, and adjust wheel in the Unisyn such that the ball floats between the lines. You now have a measure of the airflow through the front carb.
                    6. Transfer the Unisyn to the rear carb, and, without altering the wheel setting in the Unisyn, adjust the rear carb's idle speed screw until the ball floats between the two lines.
                    7. Adjust the idle mixture screws for smoothest idle. If the idle speed creeps too high or too low, adjust the front carb idle speed screw to lower or raise the idle, but NOT all the way to your desired set point. You want some of that change to come from the rear carb, too.
                    8. Keep going back and forth with the Unisyn until you have a smooth idle at your desired RPM, and both carbs read the same idle air flow.
                    9. Tighten the screw that holds the throttle coupler rod to the rear throttle lever, and verify that idle speed remains the same.
                    10. You are done!

                    FWIW, factory multi-carb setups, like the dual Strombergs on my TR6, have slack built into the throttle linkage, so that idle speed can be adjusted on each carb independently. That makes things a little easier.

                    Hope this helps.

                    Unisyn: https://www.amazon.com/Edelbrock-402.../dp/B00062YC2E
                    Gord Richmond, within Weasel range of the Alberta Badlands

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                    • #12
                      Gordy very nice wrigt up. I am helping a fellow car nut set up a set of 3 one barrels on a Chevrolet 6 with the same solid linkage. To complicate things there is a cam so not sure idle is due to cam or carbs I will use your system to see if I can make the truck run on all three carbs.
                      Hawkowner

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                      • #13
                        Originally posted by kg.works View Post
                        I purchased an Offenhauser dual carb intake and linkage some years ago and finally got to install it - or at least I am trying to.
                        I understand your dilemma, but...why?

                        If you get it perfect, what's the result? Another 10 HP? Will your 0-60 time come down from 18 seconds to 17?

                        Your money, your choice, of course. But an original engine, running right.....

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                        • #14
                          Thanks for the tips. Your ideas make sense. I'll check on the VW setups.
                          www.kgworks.ca/studeparts

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                          • #15
                            Yes, I found a lot too. But, I couldn't find any showing the Offy brand linkage setup. I did see one excellent custom setup which should be fairly easy to build if I can't get this linkage to go. If I don't use the linkage at least I'll be able to use the fuel and choke heat lines.
                            www.kgworks.ca/studeparts

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