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IAG Performance

IAG Performance IAG-ENG-1826 Stage 4 Tuff EJ25 Closed Deck Case w/Plugs, 14mm HSM, Fire-Lock, 99.75 Bore/Hone

IAG Performance IAG-ENG-1826 Stage 4 Tuff EJ25 Closed Deck Case w/Plugs, 14mm HSM, Fire-Lock, 99.75 Bore/Hone

Regular price $3,299.99 USD
Regular price $3,299.99 USD Sale price $3,299.99 USD
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IAG Stage 4 Tuff Closed Deck EJ25 converted case halves are one of IAG's strongest and most prepared EJ25 Closed Deck offering for high horsepower Subaru WRX and STIs. IAG machines the case halves assembled together in our Haas VF-4SS CNC mill to accept the IAG CLOSED Deck Inserts that transform the block into a solid deck. The unique inserts feature small passages that allow needed coolant flow to the deck surface. The case halves are then CNC machined for our new Fire-Lock head gasket solution that is loosely derived from diesel technology where a counterbore step is machined around each cylinder bore allowing specially sized fire rings to drop into the machined area and head gasket bores. The Stage 4 Tuff case is then drilled and tapped to accept 14mm head studs that combined with the IAG Fire-Lock head gasket set greatly reduces head gasket failure during high cylinder pressure scenarios. Next, the short block is Deck Plate bored and honed to 99.75mm in our in-house Sunnen SV-30 the most advanced automotive cylinder hone available. IAG's in-house honing process is able to set custom piston to wall clearances to best fit your needs. IAG's Closed Deck is suitable for street or race use and has been tested in vehicles producing 1000+ horsepower and over 55psi of boost.


This Part Fits:

Year Make Model Submodel Notes
2002 Subaru Impreza WRX
2003 Subaru Impreza WRX
2004 Subaru Impreza WRX
2005 Subaru Impreza WRX
2006 Subaru Impreza WRX
2007 Subaru Impreza WRX
2008 Subaru Impreza WRX
2009 Subaru Impreza WRX
2010 Subaru Impreza WRX
2011 Subaru Impreza WRX
2012 Subaru Impreza WRX
2013 Subaru Impreza WRX
2014 Subaru Impreza WRX
2004 Subaru Impreza WRX STI
2005 Subaru Impreza WRX STI
2006 Subaru Impreza WRX STI
2007 Subaru Impreza WRX STI
2008 Subaru Impreza WRX STI
2009 Subaru Impreza WRX STI
2010 Subaru Impreza WRX STI
2011 Subaru Impreza WRX STI
2012 Subaru Impreza WRX STI
2013 Subaru Impreza WRX STI
2014 Subaru Impreza WRX STI
2005 Subaru Legacy GT
2006 Subaru Legacy GT
2007 Subaru Legacy GT
2008 Subaru Legacy GT
2015 Subaru WRX STI
2016 Subaru WRX STI
2017 Subaru WRX STI
2018 Subaru WRX STI
2019 Subaru WRX STI
2020 Subaru WRX STI
2021 Subaru WRX STI
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