Register now to get rid of these ads!

Smoothing out carburetor throats?

Discussion in 'The Hokey Ass Message Board' started by Rocknrod, Apr 14, 2007.

  1. Rocknrod
    Joined: Jan 2, 2003
    Posts: 648

    Rocknrod
    Member
    from NC, USA

    Hi guys,

    Been doing some pondering about the intake tract, got an old carter AFB and a quadrajet on the shelf. Wondering what all tricks there are to get them to flow better.

    (Working up to designing/building a sheetmetal intake with 8 webers for a SBC.)

    Does the criss cross pattern on a throttle plate serve a purpose? What should I use to smooth out the casting flash, and little overhangs that are inside the throat on these things?

    Thanks... been something I've wanted to learn how to do for a while.
     
  2. I bought this book awhile back and it had a whole section on improving the Quadrajet...up to 1200cfm if I remember correctly.
     
  3. Moon has two different SBC intakes for Weber carbs. With a Chevy sheet metal intake fabrication is complicated by the need to precisely locate the distributor and the water passages.
     
  4. Rocknrod
    Joined: Jan 2, 2003
    Posts: 648

    Rocknrod
    Member
    from NC, USA

    Yup...

    Got a CNC mill up at work, gonna make flanges and some end plates so it all lines up.

    Cool book, I'll check it out.
     

  5. strombergs97
    Joined: May 22, 2006
    Posts: 1,888

    strombergs97
    Member
    from California

    Hello..I don't think smoothing or getting out the dings are of importance..remember that roughness and dings cause the air & fuel to bounce around which will give you better atomizing (sp)..to mix better..
    Now that worth 4 cents..
    Duane
     
  6. Bugman
    Joined: Nov 17, 2001
    Posts: 3,483

    Bugman
    Member

    You want smooth flow in the carb, Everything below the throttle plates should be slightly roughed up(80-120 grit)
     
  7. Rocknrod
    Joined: Jan 2, 2003
    Posts: 648

    Rocknrod
    Member
    from NC, USA

    Question... What do you guys think about the mesh screens for keeping fuel atomized?

    I like em just cause you can drop something down the throat and not have to pick it outa the piston and head...
     
  8. Bruce Lancaster
    Joined: Oct 9, 2001
    Posts: 21,681

    Bruce Lancaster
    Member Emeritus

    Get that Vizard book! The Q-jet improvement article is amazing, first detailed cleanup of basically stock carb, then bigger throttles...huge increases in flow WITHOUT enlarging venturis, meaning more flow without the problems of too much carburetion. It also contains a very interesting buildup of an IR Chevy, using some kind of Weber Japanese clone carbs.
    Applying that flow article to a Stromberg or a 94 would be an interesting excercise...
     
  9. Digger_Dave
    Joined: Apr 10, 2001
    Posts: 2,517

    Digger_Dave
    Member Emeritus

    Reminds me of the little "add on" gadget my old man tried on his '51 Ford way back when.
    It sat between the bottom of the carb. and the manifold.

    It was just a piece of "mesh screen" with a little propeller in the middle of each barrel.
    It was SUPPOSED to improve gas mileage; - by atomizing the fuel - but after using it a year, and keeping close records on fuel consumption - he "pitched" it!

    Said, "If anything fuel consumption INCREASED!!" (figured it got in the way!!)
     
  10. Skankin' Rat Fink
    Joined: Jun 18, 2006
    Posts: 1,496

    Skankin' Rat Fink
    Member
    from NYC

    So ... that would pretty much be the grandfather of that dumb "Turbonator." Sounds like the same old story.
     
  11. r8odecay
    Joined: Nov 8, 2006
    Posts: 787

    r8odecay
    Member





    Have pulled many of them off the top of pistons while looking at mangled cylinder bores on Harley motors....
     

Share This Page

Register now to get rid of these ads!

Archive

Copyright © 1995-2021 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.