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Q-jet carb

Discussion in 'The Garage' started by aknight_sa, Oct 31, 2006.

  1. aknight_sa

    aknight_sa 1/2 ton status

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    hi all,

    i have a question about the carb installed on my Big Block engine..

    its Rochester Quadrajet identification number is 17080213 then there us (3263 CPX), i have read in some pages on the net that this carb is for 350 engines.. not for 454... is this true? and how much CFM does this carb give?

    thanks
     
  2. ryan22re

    ryan22re 1/2 ton status

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    170 = Rochester carb, 1976 and up
    80 = 1980
    2 = 49 state emissions
    1 = Chevrolet
    3 = manual transmission

    I would say it's a 750 cfm, because its a chevy, but I dunno for sure. As far as I can tell there are no differences between the sb and bb carbs from that era (1976 and up).
     
  3. aknight_sa

    aknight_sa 1/2 ton status

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    is there a difference in the models for manual and auto transmission carbs??
     
  4. dyeager535

    dyeager535 1 ton status Premium Member

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    Almost every single Q-jet out there is different in one form or another, but an obvious physical difference? Not likely.

    There is a way to tell the CFM on the carbs It is either a 750 or 800CFM, typically plenty for any stock/moderate engine build.

    There is a link to Quadrajet info (including the difference between 750 and 800 CFM units) on my website, linked below.
     
  5. aknight_sa

    aknight_sa 1/2 ton status

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    thanks for info and good info you have on your site..

    this might sound like a silly question.. in the ID number of the q-jet the last digit is for either an even or an odd number which means euther auto or manual transmission... is this refered to the car's transmission or the choke as manual or electrical??
     
  6. dyeager535

    dyeager535 1 ton status Premium Member

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    transmission

    choke variations were pretty extensive among the various divisions
     
  7. aknight_sa

    aknight_sa 1/2 ton status

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    would it make any difference if a manual transm. carb was installed on an auto transmission car?
     
  8. dyeager535

    dyeager535 1 ton status Premium Member

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    Probably not that you'd notice.

    Something was more than likely different, such as the air valve tension or power piston spring.
     
  9. diesel4me

    diesel4me 1 ton status Premium Member

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    one more thing..

    Most "manual tranny" carbs lack the hookup for the detent cable for an automatic too..can be added though,using parts from a carb that was meant for an automatic..most of the Q-jets I rebuilt on manual tranny trucks had slightly richer jetting than those used on an automatic tranny..:crazy:
     

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