Holley 1850-5

Discussion in 'Fuel and Air Systems' started by Kendog 170, Oct 12, 2018.

  1. Kendog 170

    Kendog 170 Member

    Messages:
    10
    Likes Received:
    0
    Joined:
    Mar 10, 2016
    Location:
    Tewksbury Ma.
    Local Time:
    5:02 PM
    Hi All,
    I just inherited a Holley 1850-5 it has vacuum secondary's . Has anyone used this on a 340 4 spd ? I always liked mechanical secondaries myself. Also 600 CFM. It's a street car no strip but maybe a touch small with 20 over with Eddy heads . I am looking for some gas mileage .My AVS is giving me issues after a rebuild so I thought I might try it. I'm thinking Looking for a few opinions.
    Thanks
     
  2. JBurch

    JBurch Well-Known Member

    Messages:
    1,441
    Likes Received:
    513
    Joined:
    Oct 17, 2009
    Location:
    Owego, NY
    Local Time:
    5:02 PM
    Try it, the worst that will happen is you'll hate it; OR, you'll love it. Street car, just driving around, enjoying the day, the ride, it will work just fine. Tuning will be required for secondary opening and pump shot.
     
    • Like Like x 2
    • toolmanmike

      toolmanmike FABO Staff Staff Member FABO Gold Member

      Messages:
      31,007
      Likes Received:
      13007
      Joined:
      Jan 18, 2006
      Location:
      Iowa
      View My Photos
      Local Time:
      4:02 PM
      What's your AVS doing or not doing
       
    • brian6pac

      brian6pac Well-Known Member

      Messages:
      2,835
      Likes Received:
      1378
      Joined:
      Nov 15, 2016
      Location:
      N.E.Ohio
      Local Time:
      5:02 PM
      I like the AVS myself but the 1850 is a great carb also and will most likely need some tuning to get it perfect, it's a universal carb and that's why a lot of people don't like them, sometimes they don't work right out of the box you have to tune them.
       
      • Agree Agree x 1
      • toolmanmike

        toolmanmike FABO Staff Staff Member FABO Gold Member

        Messages:
        31,007
        Likes Received:
        13007
        Joined:
        Jan 18, 2006
        Location:
        Iowa
        View My Photos
        Local Time:
        4:02 PM
        or you can mess up the accelerator pump springs and get a off idle bog that can't be tuned out. Could be something simple with your rebuild.
         
      • rumblefish360

        rumblefish360 so close yet so far away

        Messages:
        32,155
        Likes Received:
        4406
        Joined:
        Jun 21, 2005
        Location:
        New York, on a Island
        View My Photos
        Local Time:
        5:02 PM
        I have run both carbs and they performed in the 1/4 about the same and I have gotten the same mileage out of both of them on a mildly built 318.
         
        • Like Like x 1
        • AJ/FormS

          AJ/FormS 367 FormS clone 3.09-1.92-1.40-1.09-.78od 3.55s

          Messages:
          14,179
          Likes Received:
          3589
          Joined:
          Jan 19, 2014
          Location:
          South-Central Manitoba,Canada, 900ftelevation
          View My Photos
          Local Time:
          4:02 PM
          I tried it on a 360 4-speed; not nearly big enough. So I modded it lean on the primary side and it became my hiway carb.I fattened up the secondaries a tad to average it out at WOT, and it makes enough juice to pass.
          I agree that the DP is a better manual-trans option. We don't have the Torque-multiplying fluid coupling advantage, nor the slip from idle to stall, So if you're down there, and the tires won't spin, it's a bit of a wait to get to where the power is. And that is where the DPs shine; a lil toe on the clutch and stomp on it and G-o-n-e is you.
          With a 360, just stompit.
          Theoretically it is big enough, for the stock 340
          Depending on your cylinder pressure, it can make or break your combo.Modding it lean is not for the faint of heart. That is much easier done with a metering-rod carb, if you can get a kit for it..... like the Edelbrocks.
           
          Last edited: Oct 12, 2018
        • Kendog 170

          Kendog 170 Member

          Messages:
          10
          Likes Received:
          0
          Joined:
          Mar 10, 2016
          Location:
          Tewksbury Ma.
          Local Time:
          5:02 PM
          Thanks for all the responses. I guess it can't hurt to try it out. Give me time to see whats up with the AVS .
           
        • Kendog 170

          Kendog 170 Member

          Messages:
          10
          Likes Received:
          0
          Joined:
          Mar 10, 2016
          Location:
          Tewksbury Ma.
          Local Time:
          5:02 PM
          Actually I now think the carb is fine. I just went through the motor, 20 over KB pistons ,Same crank, same cam, Eddy heads 60175, Motor sounds good at idle but acts like a severe vacuum leak or like timing marks are off. Stalls , won't accelerate properly. I know I aligned it correctly for stock setting. Timing is at 8 BTC 35' Total. Motor was tired but ran good but sat 10 years before rebuild.New Gas tank and stock fuel pump . I have 15 in. of vacuum at idle .Not sure if this is low for stock 1968 4 speed cam but can't recall what it use to run at . Comp to me is little high at 180 . In the process of moving so it's been hard to get to work on it. Have no Mopar mechanic friends to help .
           
        • Kendog 170

          Kendog 170 Member

          Messages:
          10
          Likes Received:
          0
          Joined:
          Mar 10, 2016
          Location:
          Tewksbury Ma.
          Local Time:
          5:02 PM
          My machinist who did my 500 inch stroker closed shop so I tried to do this myself (probably a mistake) but I have done a couple of prior successful builds .
           
        • toolmanmike

          toolmanmike FABO Staff Staff Member FABO Gold Member

          Messages:
          31,007
          Likes Received:
          13007
          Joined:
          Jan 18, 2006
          Location:
          Iowa
          View My Photos
          Local Time:
          4:02 PM
          If it were me I would try 15° initial timing or so and see if it likes it. If it kicks back against the starter back it down a degree or two. If it pings you can usually tune that out with the advance and the total mechanical advance in the distributor. Once you find that happy initial timing, you can always pull the distributor and send it out for a custom curve. I don't ever remember running a Mopar engine at stock timing specs and never less than 10°.
           
          • Agree Agree x 1
          • AJ/FormS

            AJ/FormS 367 FormS clone 3.09-1.92-1.40-1.09-.78od 3.55s

            Messages:
            14,179
            Likes Received:
            3589
            Joined:
            Jan 19, 2014
            Location:
            South-Central Manitoba,Canada, 900ftelevation
            View My Photos
            Local Time:
            4:02 PM
            What Mike said
            but instead of setting the timing to a number, You might try just pulling on the Vcan until the rpm peaks and then retard it enough to lose 100 rpm. This is ballpark for an automatic car with a 2500 or more TC. It will be waaay too high for your 340 stick car at 180psi, so don't drive it too deep into the throttle. But if it likes it, you will now know in which direction to take it.

            The reason I say this is too much for your combo is because reading between the lines, I'm guessing your rear gear is 3.23s or less, and coupled with a 2.66 starter gear and guessing 26.5 tall tires, this works out to 9.17mph per 1000 rpm. Idling it down to 600 in gear, which is easily doable, this makes 5.5 mph. With so much timing now ( I'll guess about 20/25*), and 180psi, the power pulses are gonna hammer into the suspension, and the shocks are gonna transfer them into the chassis, and the car is gonna start to buck, and if you let it continue, it will rattle your fillings out.
            So this method I posted above is just for diagnostic purposes.
            Mike is right about 15* in your combo; but you have to be sure your TDC marks are actually what the engine is seeing. If she liked the Vcan pull, then prove the TDC marks. If you already have, then get another light. If you have a multi-strike ignition, you cannot use a dial-back light on it, unless it is MSD's own lite.
            With a hi-compression stick car, IMO the initial should be set quite a bit lower than an auto. The Eddy heads will let you put a pretty fast curve in there. I run mine up to 28* at 2800, from 14*@1000, then I slow it down to 32/34* at 3400. This lets me run 87E10 without detonation. The curve could be a lil faster yet, but at 180psi, there is so much power I ain't chasing after a couple of ponies at 2800. If I am at 2800, it is because I am cruising or granny-shifting, otherwise I am blasting on by.
            Happy HotRodding

            Oh right, the vacuum advance should be plumbed to the sparkport, and the PCV fully operational,and plumbed to the underside of the primary throttle valves.
            15" of vacuum sounds close actually, altho I'm betting that is not at 700 rpm
             
            Last edited: Oct 17, 2018 at 4:17 PM
          • Kendog 170

            Kendog 170 Member

            Messages:
            10
            Likes Received:
            0
            Joined:
            Mar 10, 2016
            Location:
            Tewksbury Ma.
            Local Time:
            5:02 PM
            I will start with the timing. I drove this car 100K miles with timing at 8' all in at 35' . Ran awesome. it was a Mustang eater in the 80's . You are right in assuming a 323 gear .
            I appreciate the advice as I am not the sharpest tool in the shed . It takes me awhile to get things right. I hope your all correct and my problems aren't deeper. Maybe I can get some time this weekend to play with it.
             
          • AJ/FormS

            AJ/FormS 367 FormS clone 3.09-1.92-1.40-1.09-.78od 3.55s

            Messages:
            14,179
            Likes Received:
            3589
            Joined:
            Jan 19, 2014
            Location:
            South-Central Manitoba,Canada, 900ftelevation
            View My Photos
            Local Time:
            4:02 PM
            You're sharper than you think, cuz you came to FABO.
             
            • Like Like x 1
            • Kendog 170

              Kendog 170 Member

              Messages:
              10
              Likes Received:
              0
              Joined:
              Mar 10, 2016
              Location:
              Tewksbury Ma.
              Local Time:
              5:02 PM
              Well I bumped up the timing and still have the same issues. I put the rebuilt Eddy carb back on and still the same. It seems to me I'm getting excessive steam out both exhaust pipes. I'm still running water (no anti-freeze while breaking in). No water in oil. I didn't pull the plugs but did when I did my compression check a while back and didn't notice signs of water. I guess I'll pull the plugs check for signs of water, maybe crank with plugs out, Check the balancer and confirm TDC, Thinking of pulling Intake and using the better felpro SFL1213S3 intake gasket set instead of the stock set from engine set.