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Wiseco Piston Set 99.5mm Bore

MODEL # WISK598M995AP

$588.00


  • Q: Piston Ring hone grit  ebranco88303765 months ago

    Any ideas what grit should be used when honing the cylinder for the piston rings included in this kit?
  • Q: Wisco Subaru STI forged pistons   Sguimond7 months ago

    Will the factory Subaru ring fit these forged 99.5 pistons?
  • Q: Piston to wall clearance with stock size pistons  Ben8 months ago

    Just wondering what kind of piston to wall clearance's can I expect on the stock size pistons? Are all pistons made within a specific tolerance for the stock size bore? If so what size are the pistons?
    • 0 of 0 people found the following answer helpful

      A:  The piston to wall clearance is 3.5 to 4 thousandths with these pistons they are made out of 2618 forged aluminum they do have more clearance to allow for expansion of the material. As the OEM pistons are cast and do not expand the piston to wall clearance is 1 to 2 thousandths.

      Jared A. @ RallySport Direct 7 months ago  
        
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  • Q: Piston rings  Carfreak651 year ago

    Are these rings pre filed or do I need to machine them before install??
  • Q: A and B piston sizes  Steve2 years ago

    I'm going to have someone do it for me but I need to ask before any purchasing, do I have to worry about A and B piston sizes or are these pistons just a one size and all I need to do is hone? Ej25.
    • 0 of 0 people found the following answer helpful

      A:  You do not need to worry about A and B piston sizes. These are a 99.5 mm piston and will drop into the EJ25 series motor as long as nothing has been bored out, you are correct in needing to hone.

      Tyler G.
        
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  • Q: Side clearence??  BrycenSpen3 years ago

    Do these pistons drop right into a 99.5 stock bore or do you have to have your bores machined to the required side clearance?
  • Q: piston strength   Marseth3 years ago

    How much hp can these pistons handle? I'm only looking to upgrade my pistons to these without upgrading any other internals
    • 0 of 0 people found the following answer helpful

      A:  There is no official power rating on these pistons. You will achieve more power with proper upgrades to the rest of the internal parts of the motor and tuning.

      Brady R @ RallySport Direct 3 years ago  
        
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  • Q: New Shortblock  04sti8085 years ago

    I just ordered an OEM EJ257 shortblock, threw a rod bearing in my last one. Will these pistons drop right into an OEM brand new short block?
  • Q: 2009 wrx  talbot_252209886 years ago

    Will these drop in a stock engine? are there any other supporting mods required?
    • 0 of 0 people found the following answer helpful

      A:  These are OEM spec but anytime you swap parts with such high tolerances having a machine shop do the measurements and installation is always strongly recommended.

      Nick S. @ RallySport Direct 6 years ago  
        
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  • Q: Sti 07  2007 sti6 years ago

    What is the power rating on these?
    • 0 of 0 people found the following answer helpful

      A:  These pistons do not have any sort of official power rating. We do have several customers that are running 500-550 WHP on their street cars with this piston. This all depends on the proper assembly of the motor and tuning however. Thank you.

      tempemail55c523d5caae525b088b4bb3 @
        
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