What Would Be the Difference Between a Factory A/T and Manual Trans. Carb?

Discussion in 'Fuel and Air Systems' started by dibbons, Nov 9, 2018 at 3:47 PM.

  1. dibbons

    dibbons Well-Known Member

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    For example, I see on Ebay there is a Thermo-quad listed for manual transmission. My vehicle is automatic. Thank you.
     
  2. 67Dart273

    67Dart273 Well-Known Member

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    Some had a throttle return "dashpot" might be differences in non vs kickdown linkage. I don't know, otherwise, there is even a possibility of jetting changes
     
  3. RichB

    RichB CherryCuda65

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    I have also wondered about that but never saw a difference. Since there is a difference in idle settings, my guess is the factory settings are different. I want to see if anybody knows the answer.
     
  4. pishta

    pishta I know I'm right....

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    fast idle speed for an AT is going to be ~50-75 RPM higher.
    Vacuum kick orifice size is different between carbs, whatever that does on an AFB.
    Get an Carter rebuild kit that covers multiple carbs and there will be all kinds of specs for float height, choke pull off gap, etc. I would think maybe an AT would be a tad richer too for the convertor load?
     
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    • crackedback

      crackedback FABO Gold Member FABO Gold Member

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      Jetting on occasion as well was different.