What to do?

Discussion in 'High Tech Retrofits' started by Pburback, Feb 27, 2013.

  1. Pburback

    Pburback New Member

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    I've been wanting to upgrade my 81 Z to fuel injection. Can't afford to go with a LS swap. A friend of mine gave me a 99 Tahoe with a 5.7 vortec,4l60e,wiring harness & ECM,which I think will be a dollar down swap. I mean I already have the major component's,I can do the work myself. What are the opinions of doing this swap? I know it's not the most desirable swap but I won't have to starve just to get fuel injection. Please give me some feedback!
     
  2. 73Z

    73Z Veteran Member

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    Are you planning on keeping it stock. If not then steer clear do to tuning issues with that ecm. If you are not dead set on keeping the overdrive then you could make enough money selling that drivetrain to fund most of an ls swap. You can get good 5.3's all day without harness for under $500 and with for under $1000. Or if you already have a engine in the car sell the carb setup and the 5.7/4l60 drivetrain. Then you could by an Atomic or Fast EZ efi kit. You will need to change your fuel system but that will be the same no matter which efi route you decide to go so it will be a wash. Also the 5.7 vortec engines are notorious for leaky intake gaskets so check those out before you throw it in. good luck you definately wont regret going the efi route, it is worth every penny.
     
  3. 70 gsconvt

    70 gsconvt Veteran Member

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    Why do you have to have fuel injection? Maybe a new q-jet from Holley or Jet Performance will make things better. Even when you read all the articles in all the car magazines, when they do an LS build, they always get the most horsepower by yanking the EFI and putting on an intake and carb.
     
  4. sbca96

    sbca96 Veteran Member

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    If I am not mistaken a '99 Vortec has all the woes/costs of an LSx swap but
    none of the benefits. You would be better off with an LT1, its a bolt in swap
    no pan issues or other weirdness. If you want EFI....

    Regardless an EFI swap isnt cheap.

    There is no way to cheaply use that 4L60E, the controllers are damn near a
    $1000 dollars. So if you arent using the PCM, your screwed out the gate.

    I would suggest the standard carb upgrades to your original engine, and add
    a solid 700R4 trans to sweeten the deal.

    Sell the Vortec stuff to pay for the add ons/700R4.

    Tom
     
  5. BondoSpecial

    BondoSpecial Veteran Member Lifetime Gold Member

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    That is the best, most concise explanation you could get. The 1999 PCM is close to if not the same one that the LSx uses, except the vortec has cheap, goofy poppet style fuel injectors (pretty much mandatory to put a retrofit solenoid injector kit on to give it real injectors.) I swapped from a 5.0 to a 5.7 vortec in my 1999 truck, and I tuned it myself, so I am pretty familiar w/ the EFI system. If you have specific questions I can try to help. You would need to use the 4L60E (hope its a 2wd) or have it reprogrammed with a custom tune to eliminate the transmission stuff, and you would need to use all the o2 sensors (a 305 vortec has 3, I think a 350 vortec might have four). Basically the way the engine and its sensors and ecm are wired in the truck would need to stay exactly the same in the car. Is the truck in good shape? A vortec powered truck is a nice driving vehicle, I would not ruin one just to put it in a 2nd gen.
     
  6. Pburback

    Pburback New Member

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    The original engine has a bad rod knock. The reason for wanting to do the swap is not horsepower, it's driveability,reliability. The donor truck has been rolled,so that's not an option. Did I forget to mention the truck was free?And yes the truck is 2-wheel drive.
     
  7. sbca96

    sbca96 Veteran Member

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    Again, as far as I know the Vortec IS an LS platform, so you have the same
    issues as an LS1 to make it fit, except a taller intake. That means you need
    an F-body pan, special mounts .. etc, not too mention the EFI tank and all
    the assorted mods. Building a solid carbed engine will be cheaper than that
    install and will make more power. Reliable is relative, you can make a great
    carbed engine if you keep the goal within reason. Add a 700 trans and you
    will get the better drive-a-bility. It depends on your budget. You need a PCM
    to operate that 4L60E trans. If you REALLY want EFI, sell the engine to a
    truck guy who needs that setup and buy an LT1/4L60E combo. Use my EFI
    install thread to make the swap. Horsepower is more with the LT1 than the
    Vortec and the power band is set for a car install.

    1999-2000 is rated at 255 hp, later models (to 2006) at 270-285 which gets
    you to the LT1 HP range.

    A Vortec just isnt worth the effort IMO.

    Tom
     
  8. 70 gsconvt

    70 gsconvt Veteran Member

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    You could also put a 200-4R trans in the back. No electronics and there are millions of them out there. All you need is a TV cable hookupto a carb/EFI and juice for the lockup function. I have mine on a switch and only use it when I'm on the highway. It's a great trans and they can be built to withstand a ton of punishment.
     
  9. BonzoHansen

    BonzoHansen Administrator Lifetime Gold Member

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    99 'vortech 5.7' is a 1pmc sbc, probably with no fuel pump provision, not ls platform. but i think you are right that the effort is the same as other efi but the value here is low.

    but the free drive train is nice
     
  10. camarochevy1970

    camarochevy1970 Veteran Member

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    I would have to check, but I thought on my 96 tahoe, which should have the same vortech 5.7, I thought I had a fuel pump block off on there, which made me think it may have provisions for mechanical pump.

    Unless the general just used the blocks to use what was left over
     

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