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225 th350 questions

Discussion in 'Flat Fender Tech' started by cjsammyowner, Dec 27, 2009.

  1. cjsammyowner

    cjsammyowner Member

    I have a 225 buick v6 to swap into my flat fender and i have a th350 from a 4x4 74 chevy 1/2 ton with a 350 cid. How would 1 make this swap work. I do know that the 225 is externally balanced and matched with the flywheel. However the th350's flexplate does not match the balancing needed for the 225. Is that correct? So if the balancing is needed how do I get the swap to work as it should?
     
    cjsammyowner, Dec 27, 2009
    #1
  2. Patrick

    Patrick Super Moderator Staff Member

    I'd get a BOP TH350 so it'll bolt to the 225, and get a flexplate for a 225.
     
    Patrick, Dec 27, 2009
    #2
  3. bobracing

    bobracing web wheeler

    225 need an odd fire flexplate, IIRC a 231 oddfire FP will work, sure I will be corrected if not.

    An adapter similar to this will adapt the trans. Just make sure it works with an auto (not sure on this one but have seen them work).
    http://www.jegs.com/i/JEGS/555/60170/10002/-1?CT=999

    Having a 4x4 (shortshaft) trans will make for the longer adapter, just be aware it's going to be longer than the adapters that use a new output shaft.
     
    bobracing, Dec 29, 2009
    #3
  4. Patrick

    Patrick Super Moderator Staff Member

    Or, like I said, use a BOP trans. and
    A flex plate from a 225.
     
    Patrick, Dec 29, 2009
    #4
  5. bobracing

    bobracing web wheeler

    The Chevy 4x4 trans might be an easier conversion, if the trans is good, it won't need to be torn down for a new output shaft, it's all a bolt in operation.

    Also being a factory 4x4 trans, it's probably the "K" case, with extra strength built into the tail housing.

    Just saying $50 might be a cheap way to make things fit with acquired parts. Now of course this will also depend on which adapter is used and if the trans is any good.
     
    bobracing, Dec 30, 2009
    #5
  6. Patrick

    Patrick Super Moderator Staff Member

    True, but I personally wouldn't install a used tranny without rebuilding it first anyway, unless I knew it's history.
     
    Patrick, Dec 30, 2009
    #6
  7. junkfood

    junkfood Member

    The fluid in the torque converter should work to balance the odd fire, but an odd fire flex plate wouldn't hurt. It makes a long combination for a flatty but it is doable. Might want to check out Novaks Th350/D18 adapter. It's a little longer and helps prevent the front driveshaft issues.
     
    Last edited: Dec 30, 2009
    junkfood, Dec 30, 2009
    #7
  8. cjsammyowner

    cjsammyowner Member

    would i have issues with a stock 1970 cj front driveshaft from a v6 model? i know their skinnier than the 4 cyl ones.
     
    cjsammyowner, Jan 1, 2010
    #8
  9. nickmil

    nickmil In mothballs.

    It will be too short but could be lengthened. The u-joints and yokes are much smaller and weaker. I'd stick with the larger joint. Early Waggy's had a small shaft and the larger 153x U-joint and would be a better choice imho.
     
    nickmil, Jan 1, 2010
    #9
  10. bobracing

    bobracing web wheeler

    Again it depends on what adapter you use, ask before buying the adapter.
    Generally the short adapters need the smaller U-joint or I heard grinding on the trans case will work. The longer ones allow use of the larger U-joints.
    Both will have trans pan clearance issues, more or less depending on how you install the drivetrain combo.
     
    bobracing, Jan 2, 2010
    #10