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Carb. on a 90' K5

Discussion in 'The Garage' started by tiger9297, Nov 6, 2004.

  1. tiger9297

    tiger9297 1/2 ton status

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    Carb. on a 90\' K5

    About to put an engine in my 90' K5. Stock TBI is pathetically weak as you know. Multipoint systems are expensive. The computer controls so much on this truck is a carb. even a possibility? I drive this truck alot so it has to be reliable. I can't have everything "rigged" to make it work. What do you think? /forums/images/graemlins/1zhelp.gif
     
  2. sapper

    sapper 1/2 ton status GMOTM Winner

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    Re: Carb. on a 90\' K5

    There was a girl here that bought a 90 and the PO had put a new minfold and carb on it and it sucked. He didnt bother to change the fuel pump or tank so the carb had way to much presure for it and i beleive that the baffles in the tank are different. I have a 89 with the stock TPI and i dont think thats your problem, if you think thats why its weak, I'v been out with guys running big blocks and where they have trouble due to carbs i can run over the same thing with no problems.
     
  3. shaun

    shaun 1/2 ton status

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    Re: Carb. on a 90\' K5

    I put a carb on my 90 and it is awesome. Put a mallory three port regulator and a fuel pressure gauge inline. Tune it to 8 psi (with tbi pump, tank, and filter), 85 hei dist, cap, rotor, new intake and edelbrock 600, and new heads. She purrs and has more power than my tbi ever did. (didnt touch the block.) Also changed to v belts and a standard rotation w/p.
     
  4. tiger9297

    tiger9297 1/2 ton status

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    Re: Carb. on a 90\' K5

    mallory three port regulator?? i don't mean to ask a stupid question but i'm not really sure what that is? where do i get it? how much? also, what do you do about all of the computer stuff. from what im told everything runs off the computer. Transmission, even the speedometer i'm told runs off the computer. I don't want all my dash lights and everything going crazy if i go with a carb. Thanks for your help. I just want POWER!! /forums/images/graemlins/peace.gif
     
  5. pauly383

    pauly383 Daddy383 Staff Member Moderator

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    Re: Carb. on a 90\' K5

    Stay injected . I am a carb diehard , only for lack of funds . TBI doesn't have to make lots of power , its a truck , you want reliable go anywhere truck , you leave it injected and add a couple bolt on power mods , without having to reengineer stuff to work for you . Someday I will be injected on both trucks . The engine you have could still move the truck really well with the TBI . Just my honest opinion /forums/images/graemlins/k5.gif /forums/images/graemlins/k5.gif
     
  6. rcamacho

    rcamacho 1/2 ton status

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    Re: Carb. on a 90\' K5

    I'm also running a return style fuel regulator and carb on my 402 with the stock EFI pump and tank. Works fine.
     
  7. tiger9297

    tiger9297 1/2 ton status

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    Re: Carb. on a 90\' K5

    If I go with a carb. what do I do about disconnecting all of the computer stuff. Won't my computer be "looking" for things that aren't there. Even my speedometer is calibrated through the computer according to the GM guys. A carb could be simple BUT it could also be a headache if lights are blinking and things don't work right b/c the computer is confused.
     
  8. pauly383

    pauly383 Daddy383 Staff Member Moderator

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    Re: Carb. on a 90\' K5

    Your lighting , starter , alternator , all should be fine . The speedometer may work , I don't know . But why are you wanting to remove the TBI ?
     
  9. dyeager535

    dyeager535 1 ton status Premium Member

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    Re: Carb. on a 90\' K5

    You'd have to replace your distributor for one thing, and secondly, yes, your speedometer will no longer work, which is doubly problematic because you can't just bolt a speedometer cable onto your t-case without even more parts.

    TBI isn't pathetically weak, but it CAN be a restriction on a built engine. *Tuned* the TBI isn't going to be any worse power-wise than a carb.
     
  10. tiger9297

    tiger9297 1/2 ton status

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    Re: Carb. on a 90\' K5

    i don't necessarily want to remove the TBI. In fact i'd rather keep it but im about to rebuild the engine and it only flows 470CFM I think. I plan to build a pretty stout engine. would like to anyway. This TBI just won't feed it. I realize that I can go with a multi port system but they are so expensive I was going to use that as a last resort. I wish i could find a good 700+ CFM TBI similar to stock. Then I could just replace the manifold, hook up new TBI and reprogram chip. Good to go. (I think) /forums/images/graemlins/dunno.gif
     
  11. shaun

    shaun 1/2 ton status

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    Re: Carb. on a 90\' K5

    just use a 454 plenum(bottom part of the tb) with your injectors. This is basically like putting on a 600 cfm tb in its place. With my carb swap I rewired my whole truck with a painless, replaced all ignition psrts and did alot more work then it seems like you want to do so just keep it tbi and save time and money
     

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