10bolt vrs 12bolt

Discussion in 'Transmission & Driveline Topics' started by slayer74, May 5, 2014.

  1. slayer74

    slayer74 Veteran Member

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    recently picked up a 76 with a 383 stroker,guy claims it pushes out 450hp it currently has a 10 bolt 3:90 posi with that kind of hp should i upgrade to a 12 bolt? any thoughts sean
     
  2. Gary S

    Gary S Administrator Lifetime Gold Member

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    Don't worry about the strength of the 10 bolt. In original trim, it is almost equal to an original trim 12 bolt in strength. If you need more, upgrade your 10 bolt with stronger parts rather than spend tons more for a 12 bolt.
    The weakest spot on a 10 bolt is the axle tubes where they are welded into the center section.
     
  3. big gear head

    big gear head Veteran Member

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    You can upgrade the 8.5 10 bolt to 30 spline axles. If you put sticky tires on it you need to read the thread about welding the axle tubes. This should be done by a professional.
     
  4. Bumpad_Z28

    Bumpad_Z28 Veteran Member

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    10 bolts (8.5") version are plenty strong enough for almost every application !!! Including 450 HP 383's :)

    "I" just found a deal on a 12 bolt so I pulled the trigger and won't have to worry about it again.

    ~DaVe
     
  5. Coadster32

    Coadster32 Veteran Member Lifetime Gold Member

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    If it helps...I have a383 stroker supposedly dyno'd at 525 @ flywheel, (who really knows). Anyhow I use a 10bolt 8.5 rear with 5:12's and posi. Beat the heck out of it w/o any problems.
     
  6. Ihada70Z28B4

    Ihada70Z28B4 Veteran Member

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    The Grand Nationals came with the 8.5 and they are known to hold up just fine to alot more than that. I have seen plenty of 9-10 sec cars with upgraded axles and c clip eliminators.
     
  7. Protour-Camaro

    Protour-Camaro Veteran Member

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    This is like a BBC vs a SBC arguement. If you build the 10 bolt right, it will hold up. I wouldnt be so ingornat to say "I have a 12 bolt, I never have to worry again"....pssss...its not that great
     
  8. slayer74

    slayer74 Veteran Member

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    wow! thanks for all the info,i'm gonna go with with the old "if it aint broke dont fix it"rule of thumb for now thanks again
     
  9. Bumpad_Z28

    Bumpad_Z28 Veteran Member

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    just more 12 bolt envy ... maybe it's not that great, but it's not iGNorant :confused: either ;)
     
  10. Rich Schmidt

    Rich Schmidt Veteran Member

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    Dave Henninger and Kurt Urban ran their blue 70 Camaro into the 8's with their 8.5" 10 bolt and never had issues. As far as welding the axle tubes,the 12 bolt has the exact same tubes,and they need to be welded too,so there is no difference there. Theyuse all the same size bearings,and the 10 bolt uses 10 7/16" bolts to hold the ring gear on which is techincally more bolt then the 12 bolt's 12 3/8" bolts. Aside from the 28 spline axles,there is no real difference.
     

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