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Carb recomendation?

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by Fry, May 25, 2004.

  1. Fry

    Fry 1/2 ton status

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    I was planning on building a motor for my blazer but due to lack of funds I think I'm just going to "freshin" up the 305, basically stock with a cam and intake, very mild something to get decent mileage out of and maybe a bit of a horsepower gain.
    Anyway what carb should I look for? The rochester on there is crap so I don't want to rebuild it again so that option is out.
    Thanks
     
  2. Grim-Reaper

    Grim-Reaper 3/4 ton status Author

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  3. Fry

    Fry 1/2 ton status

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    a reman? Brand Suggestions? CFM?
    Really wanted to build a motor but I think I'll hold off on it and go newer FI later down the road.
     
  4. imiceman44

    imiceman44 1 ton status

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    [ QUOTE ]
    a reman? Brand Suggestions? CFM?
    Really wanted to build a motor but I think I'll hold off on it and go newer FI later down the road.

    [/ QUOTE ]

    Any stock or modified QJet would be the best.
    I can't recommend any of the usual places since there is never a gurantee, but I know BG makes awesome rebuilds but they ain't cheap.
    /forums/images/graemlins/peace.gif
     
  5. xnoahx

    xnoahx 1/2 ton status

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    ive got an edelbrock preformer RPM q-jet, its 850 CFM for sale, $300
     
  6. camiswelding

    camiswelding 1/2 ton status

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    edelbrock quad replacement...I cant remember if the 850 is the right one specd for the 305,,,, is it?
    cam
     
  7. 75-K5

    75-K5 3/4 ton status

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    850 seems HUGE for a 305, but the Q-Jet's small primaries should help.
     
  8. Z3PR

    Z3PR Banned

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    [ QUOTE ]
    I was planning on building a motor for my blazer but due to lack of funds I think I'm just going to "freshin" up the 305, basically stock with a cam and intake, very mild something to get decent mileage out of and maybe a bit of a horsepower gain.
    Anyway what carb should I look for? The rochester on there is crap so I don't want to rebuild it again so that option is out.
    Thanks

    [/ QUOTE ] I highly recomend "freshin up" a 350 and forget about that 305. I've bought used (Running) 350's for $200.00 or less. Our trucks are all about torque, and a 305 just doesn't make anough torque. /forums/images/graemlins/deal.gif
     
  9. ratzila

    ratzila 1/2 ton status

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    I'm running a Jet-performance stage 2 quadrajet.Its 800cfm and I'm running it on a 454. I'm satisfied with it. I used to run a BG 750 speed demon that I heard actually flows at 830. I could only get 2 mpg in town and 5 mpg on the highway in my 91 blazer. With the q-jet I'm getting 8mpg in my burb.
     
  10. madmike

    madmike 1/2 ton status

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    I'm also running a JET Quadrajet on my '74 K10 with a 489 bbc. The truck runs real well on and off-road, and I get 10 mpg on the highway!
     
  11. alf4444

    alf4444 1/2 ton status

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    I've got a jet stage 2 taking up space if you want it $200 plus ride. Nearly new less than an hour on it (I went a different direction /forums/images/graemlins/grin.gif)and Jet will recalibrate it for your application for $75. They are $360 new
     
  12. 84_Chevy_K10

    84_Chevy_K10 Banned

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    [ QUOTE ]
    850 seems HUGE for a 305, but the Q-Jet's small primaries should help.

    [/ QUOTE ]

    GM put 795 cfm q jets on 4.3L V6's. The vacuum door on the carb will only open if the engine needs that much air.

    Due to the nature of the design, you can disreguard any CFM numbers on a Q-jet. They only came two sizes anyway--750 and 795. The 850 is in the aftermarket.

    If I'd known now what I new when I bought my carb three years ago, I wouldn't have spent a dime on it. I certainly wouldn't spend a dime on a 305, either.

    For the price of one new Q-jet, I'm swapping to TBI. If I had a good used Q-jet I'd probably leave it there knowing what I know now, but good used TBI setups go for about $300. All you need then is a fuel pump and you're ready to enjoy EFI--the ultimate carburator.
     
  13. Fry

    Fry 1/2 ton status

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    I have always said that I would never spend a dime on a 305, that they just weren't worth it. But it seems to make sense in my situation right now. To buy a used 350 I'd be looking at $2-500 and who knows whats wrong with it and why it was pulled, I personally think that when buying a used engine you have to at least pull it apart and rering it and replace the bearings while your there, then you might aswell bore it out and get it machined, then your already up to $1000.
    The 305 in the blazer doesn't use oil and has good compression so a cam swap, manifold cleanup and carb would do wonders. With the way it is right now its running way to rich and stumbles and is all the way leaned out on the carb and the timing is set correctly, I rebuilt the carb to try and clear the matter but it didn't help. It did on the highway get good mileage, around 18-20mpg with the 33s and 3.08s.
    I'm shooting for around $500 MAX on this motor, thats a $150 cam, $150 cam swap kit and that leaves $200 for a carb. I need something that will run good, not be too much for the motor and will start good in the winter.
    Remanufactured Q-Jets seem to be fairly expensive, any other alternatives?
    What about like a Edelbrock Reman 600cfm Electric Choke for $195.88 P#9906. Waste of money?
    I put an edelbrock on my old Chevelle and it worked great for its demands.
     
  14. 84_Chevy_K10

    84_Chevy_K10 Banned

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    I have an Edelcrap carb on my truck now. It is absolutely worthless off road.
     
  15. Fry

    Fry 1/2 ton status

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    for inclines you mean?
    Maybe if I screw around with my fuel pump (stupid electric POS) and put in a fuel pressure regulator my quadratjet might work.
    Down the road I'd like to go with a vortec or something along those lines but I got to get my truck back on the road and have a huge list of stuff and very small bank account to deal with.
     
  16. 84_Chevy_K10

    84_Chevy_K10 Banned

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    Quadrajet is the next best thing to EFI. Squarebore like an Edelbrock performer series is worthless.
     
  17. dyeager535

    dyeager535 1 ton status Premium Member

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    If the carb isn't working right, before spending dime 1 on opening that engine up, fix the carb. You might bes surprised how much more power you get with a properly working carb.
     
  18. Fry

    Fry 1/2 ton status

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    I already rebuilt it with the help of my Journeyman. Think part of the problem lies in the fuel pump. Still the 305 is gutless, maybe I'll forget touching it for now and concentrate on just getting it to run right and see if that helps out any.
    Both sides of the carb are leaned out as much as possible and I still can walk behind the truck because of the fuel fumes.
     

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