LS1 Fuel Pump in 79 Z/28 ?? Possible

Discussion in 'High Tech Retrofits' started by npersha, Mar 17, 2011.

  1. SupplySgt

    SupplySgt Veteran Member Lifetime Gold Member

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    Holy crap with me working nights I haven't checked the tech sections much. Boy am I glad I came across this!!! Great info. I really learned something today.
     
  2. anesthes

    anesthes Veteran Member Lifetime Gold Member

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    Some more info:

    1) The LS1 sending unit uses a special pump. The pump has two outlets, one being a 3/8" to the fuel rail, the other like a 1/16" "jet" which goes to the check valve in the bucket. This is designed to operate the mechanism that keeps the bucket full of fuel. IF you pick up a used sending unit and need to swap the pump, you need to either get a modified walbro from Racetronix, or work out some magic.

    2) The stock float level will hit the sending unit if you place the LS1 unit where the vent was. The LS1 sending unit has a different OHM output so the fuel gauge will not work. However, you can remove the gauge from the dash and change two resistors to get the gauge to read the same as the LS1 sender.

    Another option, if you would rather not modify the gauge, is you could replace the resistor board with a 0-90ohm unit from a '97 grand prix.

    -- Joe
     
  3. SupplySgt

    SupplySgt Veteran Member Lifetime Gold Member

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    ^^So what do ppl with 99-02 F-bodies usually do when their pumps go out? replace the pump or the whole assembly?
     
  4. anesthes

    anesthes Veteran Member Lifetime Gold Member

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    Both. You can use the racetronix pump (picture attached), modify your own walbro, or replace the whole assembly.

    -- Joe
     

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  5. SupplySgt

    SupplySgt Veteran Member Lifetime Gold Member

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    I'll probably just buy the whole assembly new when I get to that part. Right now I don't even have the car that my currently-being-built motor is gonna go into yet. Sad I know.
     
  6. tb8125

    tb8125 Member

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    Vettworks set up works well real ez almost just plug and play....
     

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    Last edited: Jul 11, 2011
  7. anesthes

    anesthes Veteran Member Lifetime Gold Member

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    Same setup here.

    What did you do about the gauge? I'm probably going to swap the two resistors like the thirdgen guys do when they run the LS1 sender.

    -- Joe
     
  8. tb8125

    tb8125 Member

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    I am using 4th gen gauge cluster... So I am going to use the 4th gen stock tank gauge.... Just hope it reads right
     
  9. usmcz28

    usmcz28 Veteran Member Lifetime Gold Member

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    How does it fit up under the car, Is there any rubbing or cutting needed to the trunk floor? Hopefully i'll be doing this to my tank here soon, just got all my misc. engine parts in the mail today. Looks like I get to reassemble the engine tonight.
     
  10. anesthes

    anesthes Veteran Member Lifetime Gold Member

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    I just need the stupid electrical connector for mine.

    -- Joe
     

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