Built 2v, Cobra crank vs GT crank

Discussion in 'General Tech' started by Tally_4.6, Aug 23, 2015.

  1. Tally_4.6

    Tally_4.6 Well-Known Member

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    Down to deciding on which crank i want to use. Built N/A 2v at first, with boost later. I want the bottom end to handle around 6-700 without a problem.

    I have the '03 GT crank ready to go, with the corresponding block on the stand.

    Boss rods with dished forged Manleys are the rest of the rotating assembly.


    Pros and cons of both? I've heard the RPMs will kill the GT crank, but it can handle a lot...and it's cast. But the Cobra crank likes to rev and is forged.


    Help...lol
     
  2. 96blak54

    96blak54 Legend

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    This all depends on the blocks ability to stay put. A cast block doesnt move like an aluminum block does. The aluminum block expanding/ contracting, twisting alot more than the cast iron. If youre using aluminum block, definitely use the flexible forged crank.

    Harmonics do play a roll in longevity and the forged will endure. But then again how many cast cranks have we heard breaking in a cast block?

    What dish piston are you going with? Is this for pi heads?
     
  3. Tally_4.6

    Tally_4.6 Well-Known Member

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    -18cc

    Gasket matched ported PI heads with cams.
     
  4. D3VST8R96GT

    D3VST8R96GT Well-Known Member

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    I second the cast crank. There are so man people who have repeated what they read about the cast crank. I think they are great for what they are.

    If its a NPI block you will need some work done to throw the forged crank in there. the centers have counter weights.
     
  5. Tally_4.6

    Tally_4.6 Well-Known Member

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    '03 block, so no work necessary.
     
  6. duff daddy

    duff daddy Legend

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    I have an 8 bolt f150 crank in my na 2v spinning to 8500 + ...it's cast
     
  7. 96blak54

    96blak54 Legend

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    Its not forced induced either. I get where you're going though
     
  8. DropTopPony

    DropTopPony Administrator Staff Member Admin SN95 Supporter

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    Use what you have. I picked up a Cobra crank for almost nothing with my Teksid block so it was a no brainer but I honestly was prepared to go ahead with the cast crank for any build I had in mind. Like said above, how many failures have there really been over the years?
     
  9. Tally_4.6

    Tally_4.6 Well-Known Member

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    Well shit.