TH200-4R ID ?

Discussion in 'The "Juice Box"' started by Kaule, Sep 14, 2018.

  1. Kaule

    Kaule Gold Level Contributor

    I got a TH200-4R and tryed to decode the ID, found some websites but don't get it right.
    ID: 338-861CRF0680

    200-4r.jpg
    valvebody.jpg
    I know there are hardened parts for this transmission, is there a way to see what parts i have, hardened or not ?
    Example the statorshaft
    statorshaft.jpg
     
  2. Golden Oldie 65

    Golden Oldie 65 Well-Known Member

    Came out of an`86 Monte Carlo/Pontiac Grand Prix LG4 305 powered car. Look for a trace of bluing on the stator support shaft in the splined area, which would indicate it has been replaced with a hardened one. Pretty much all rebuilds these days will get that piece.
     
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  3. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

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  4. Kaule

    Kaule Gold Level Contributor

    Thanks !

    Edit:/ Have pics now, is it hardened ?

    stator1.jpg stator2.jpg
     
    Last edited: Sep 15, 2018
  5. Golden Oldie 65

    Golden Oldie 65 Well-Known Member

    Yes
     
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  6. TexasT

    TexasT Texas, where are you from

    You already have it apart. Why not replace it? I'd replace those button head screws while you are at it and lock tight em in.

    I'd also pull that pump apart and put in a sonnax slide spring, and a pair of "unbreakable" rings. And swap in a larger boost valve, rev boost valve, and spring to get the pressure up.

    Another thing I'd do is pull the over pressure roll pin and slip in a washer to prevent the pin from cutting the over pressure relief spring.

    Are you going in deeper? I have more suggestions if you are.
     

    Attached Files:

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  7. Kaule

    Kaule Gold Level Contributor

    Hi Rich,

    i will rebuild the transmission to swap out the th350,
    have read your thread at ihadav8.com

    The only thing i ordered yet is a hardened sun-shell.

    For the pump i was looking at this
    https://www.ebay.com/itm/2004R-700R...5007338?hash=item1e14ed56a:g:tW4AAOxyFiRR3aP8
    The 10 vane was a suggestion from another thread.
    Don't know if the billet pump rotor that is also available is worth the $160 ?

    Can i use somthing like that for the rebuild ? ( aditional a wide band and larger servo )
    https://www.ebay.com/itm/2004R-Supe...601863?hash=item43e862dc47:g:nw0AAOSwBLlU4jWB
    https://www.ebay.com/itm/2004R-Supe...765490?hash=item43aa1bec32:g:p9gAAMXQBlJR8Eor

    I also read about a hardened forward drum, is it a "must have" and where to buy it ?
     
  8. TexasT

    TexasT Texas, where are you from

    You can go to the 10 vane pump if you like, I didn't feel it necessary. Just did the mods I suggested above. My thought is for every additional vane it takes that much volume away from the pump. Mine puts out plenty of pressure as measured with a gauge. I just pulled it apart, inspected it, put the stiffer slide spring and unbreakable rings in and upgraded the boost valves and spring. Mine was a budget build so a $160 rotor was not even considered.

    I didn't do the wide band either. Just a carbon stock width with the sonnax servo. I didn't have a way to resurface the drum and it seemed flat so I hit it with some emery cloth as mentioned in the transgo instructions and put a cross hatch pattern on it.
    I used one like this that was a BorgWarner brand.
    https://www.ptptrans.com/turbo-200-th200c-200-4r-th325-th325-4l-transmission-band-1976-1990-gm/
    https://www.ptptrans.com/200-4r-th2...tor-shaft-hardened-splines-1981-1990-fits-gm/


    You need a bushing set, I did new torrington bearings, and some mods to the plate and valve body.
    I will send you some links. Some are old and don't work some are full of info. any questions I'll send my phone numbe and you can text them if you like. Some of the info wont be posted on an open form as asked by the places I got it and these guys make a living at it so I respect their wishes.
     

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