Question for you Racers...

Discussion in 'Technical' started by T.L., Dec 6, 2006.

  1. T.L.

    T.L. Banned

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    I figure that if anyone would know, it would be you guys who race your Mavericks, since you are applying some serious torque to everything.

    I want to replace the motor-mount bolts (the ones that go into the engine block) because some threads are messed up on my originals. The originals do not have any markings on the heads, so I have no idea what grade they are. They are a 7/16" coarse-thread shouldered bolt. So what grade of bolts do I need? Grade-5? Grade-8? Do they need to be shouldered bolts, or will a standard type with a lock-washer be acceptable?...
     
  2. wagesofsin

    wagesofsin Official Lurkologist

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    grade 8, shouldered is strongest, the less threads the better, use a serrated lock washer if possible. hope that helps.
     
  3. igo1090

    igo1090 Member

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    either grade 5 or 8. lock washers. how much shoulder do you have room for? these are the bolts holding the mount to the block, correct? ive always used non-shoulder. the bolts are only maybe 1 or 1 1/4 inches long, going thru the mount (maybe 1/8 thick) and a lock washer (maybe 1/8 thick). so more than a 1/4 inch shoulder would then start to hit the threads in the block, correct? or am i misunderstanding what we are talking about here?

    anyways, grade 5 or 8 are fine.
     
  4. CornedBeef4.6L

    CornedBeef4.6L no longer here

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    Garde 5 or 8. Trust me when I say the Rubber mount will break long before either of those grade bolts lets loose.
     
  5. T.L.

    T.L. Banned

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    Yes, I am talking about the bolts holding the mount to the block. The original bolts are shouldered, so obviously I have enough room for a shoulder of that size. I was just wondering if it was really necessary. They are 7/16" standard coarse thread x 7/8" long (basically an inch). I find it interesting that there are no markings of any kind to indicate the grade.

    By the way, can anyone tell me what they are supposed to be torqued at?...
     
  6. eddie1975

    eddie1975 Windsor Specialist

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    Prolly around 35,000 INCH pounds :rolleyes:
     
  7. wagesofsin

    wagesofsin Official Lurkologist

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    being shouldered doesnt change the o.d. threads are cut into the total shoulder of any bolt. unless its a pivot, or bottoming shoulder. take what ya had, or just measure, go to the ace hardware, get a couple(or more) grade 8 hex heads, a couple(or more)serrated lock washers, and bolt it together! its that easy
    :drink:


    p.s. ya gonna actually use a torque wrench on em?
    just flatten the lock, not actually measuring depends on whos doin the tightnin'
    :yikes:

    im sure youll be fine
     
    Last edited: Dec 7, 2006
  8. RabidCustoms

    RabidCustoms sic minds demand sic toys

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    I love nylocks(y)
     
  9. wagesofsin

    wagesofsin Official Lurkologist

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    yea, me too, i mis read the post :slap:


    i thought they were askin for the motor mount bolts, any ways, just do what i said...
    :drink: sorry , i have to edit this, i have 3 carpet commandos on my ankles as i type this ( hahaha). didnt mean to come across as DO AS I SAY...

    wages
     
    Last edited: Dec 7, 2006
  10. PaulS

    PaulS Member extrordiare

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    40 to 50 Ft Lbs for a 7/16 NC bolt

    Grade 8 can be torqued as high as 70 FtLbs
     
    Last edited: Dec 8, 2006

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