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HELP !!! Austin area.. I need carb help...

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by rocko, Jun 27, 2001.

  1. rocko

    rocko 1/2 ton status

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    Ellsworth, Maine
    Anyone in the Austin area... good with tuning a carb?
    I bought a freshly rebuilt Q-jet and put it on last night.. well the truck run's alot smoother.. It doesn't have the electric choke..I'll have to take it off my old one..
    But my problem is.. it's fine until I try to open up the secondaries when hitting the pedal to the floor..
    The secondaries take forever to open..
    I need more power out of this carb...
    Anyone know how to tune one?


    A well armed society is a polite society. <A target="_blank" HREF=http://www.rocko.rockcrawler.com>http://www.rocko.rockcrawler.com</A><P ID="edit"><FONT SIZE=-1>Edited by rocko on 06/27/01 11:32 AM (server time).</FONT></P>
     
  2. rocko

    rocko 1/2 ton status

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    back to top.

    A well armed society is a polite society. <A target="_blank" HREF=http://www.rocko.rockcrawler.com>http://www.rocko.rockcrawler.com</A>
     
  3. HarryH3

    HarryH3 1 ton status Author

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    On the passenger side of the secondaries there is a spring that is supposed to be adjusted to set the rate at which the top door opens. It's been years since I had anything with a carb, so the memory is a little rusty. But I think the spring gets adjusted via a small screw on the carb and there's a tiny set screw that locks it into place. Any decent book on Q-Jets will show you how to adjust it.

    <font color=black>HarryH3 - '75 K5</font color=black>
    <A target="_blank" HREF=http://www.angelfire.com/super/ThunderTruck>http://www.angelfire.com/super/ThunderTruck</A>
    It's a great day to be alive...
     
  4. rocko

    rocko 1/2 ton status

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    Thanks Harry. I'm going to attempt to tinker with it..


    A well armed society is a polite society. <A target="_blank" HREF=http://www.rocko.rockcrawler.com>http://www.rocko.rockcrawler.com</A>
     
  5. mattman

    mattman 1/2 ton status

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    Sorry dude. Never messed with a Chevy carb. Now if it was a question with a Motorcraft 2150 or 2150A two barrel, I could at least tell how to screw it up real bad.

    90 GMC Jimmy, 350 TBI, 700R4, 32's
    84 Bronco II 204,000 miles and counting...........that's 207,000 and counting now
     
  6. 84_Chevy_K10

    84_Chevy_K10 Banned

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    Get the book on Q-Jets! They're a tough carb to tune but the best there is! I'm rounding up used Q-jets for now and one day I'm going to get the book and learn to tune them so I can make a great one! Rignt now, my Edelbrock 500 CFM 1404 will do.

    Tim
    '84 Chevy K10, lifted, loud, fast, and 3/4 ton axles
     
  7. rocko

    rocko 1/2 ton status

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    I have 3 Q-jets here... one is okay.. the other needs rebuilding and the other one is kinda in pieces..
    The one I put on my truck is in great shape.. has a rebuild sticker on it. and it's pretty recent..
    I'll keep tinkering with it..
    Phyte's Dad is in town.. And he said his dad is a carb guru.. I'll have him look at it..
    Other than that.. I'm happy with the low end performance of the carb.. just can't wait to see what difference it's going to make when I get the secondaries to open up..


    A well armed society is a polite society. <A target="_blank" HREF=http://www.rocko.rockcrawler.com>http://www.rocko.rockcrawler.com</A>
     
  8. BlueBlazer

    BlueBlazer 1/2 ton status

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    Are you sure its not the secondaries opening up too fast. Does it feel like it falls flat on its face when you floor it. If so it sounds like the secondaries are opening too fast. The screw on the side it really small, so find a little ( and I mean little ) screw driver to loosen or tighten it. There is a small allen head set screw you must loosen first. Just loosen or tighten it and take it out and try it. If it gets worse then go the other way. It sounds like its too loose though so try tightening it first. Hope this helps.

    82 K5, 6.2L Diesel, sm465, np205, 14 bolt welded, 8 lug 10 bolt lock right, 410 gears, 35" Mud Kings
    SPEAK SOFTLY AND DRIVE A BIG TRUCK
     
  9. rocko

    rocko 1/2 ton status

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    Thanks Blue Blazer..
    That's exactly what it sounds like... just goes flat when i romp on it..
    Under normal accelaration.. she's real strong.. then floor it and Nothing. !!!
    I'll give it a shot..

    A well armed society is a polite society. <A target="_blank" HREF=http://www.rocko.rockcrawler.com>http://www.rocko.rockcrawler.com</A>
     

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