Flexplate Bolt Sizes

Discussion in 'Transmission and Drivetrain Tech' started by cosworth, Apr 29, 2012.

  1. cosworth

    cosworth Well-Known Member

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    I have a 74 Duster with a 318 that was originally a automatic car, that i am putting a 3 speed manual in. I purchased pressure plate bolts that are wayyyy to small, then thinking about it I dug out my old flexplate bolts that are the right size but too short.....

    Does anyone know what size this is and where i can find them?

    May just need to run down to the hardware store these bolts are only grade 8
     
  2. cosworth

    cosworth Well-Known Member

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    I think ive figured it out posting here for somebody to correct me if im wrong.

    7/16-20RH with approx .910 Underhead bolt lenght.

    Flexplate bolts are 7/16-20 with .50 underhead
    Pressureplate are 3/8 with approx .910 underhead
     
  3. oldkimmer

    oldkimmer FABO Gold Member FABO Gold Member

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    ..........sounds about right...............kim............
     
  4. cosworth

    cosworth Well-Known Member

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    I guess they used different cranks for auto/manual cars?