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IAG Stage 4 Tuff EJ25 Subaru Closed Deck Short Block - Subaru Models (inc. 2006-2014 WRX / 2004+ STI)
IAG Stage 4 Tuff EJ25 Subaru Closed Deck Short Block - Subaru Models (inc. 2006-2014 WRX / 2004+ STI)
IAG Stage 4 Tuff EJ25 Subaru Closed Deck Short Block - Subaru Models (inc. 2006-2014 WRX / 2004+ STI)
IAG Stage 4 Tuff EJ25 Subaru Closed Deck Short Block - Subaru Models (inc. 2006-2014 WRX / 2004+ STI)
IAG Stage 4 Tuff EJ25 Subaru Closed Deck Short Block - Subaru Models (inc. 2006-2014 WRX / 2004+ STI)
IAG Stage 4 Tuff EJ25 Subaru Closed Deck Short Block - Subaru Models (inc. 2006-2014 WRX / 2004+ STI)
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User Media for: IAG Stage 4 Tuff EJ25 Subaru Closed Deck Short Block - Subaru Models (inc. 2006-2014 WRX / 2004+ STI)

IAG Stage 4 Tuff EJ25 Subaru Closed Deck Short Block

Subaru Models (inc. 2006-2014 WRX / 2004+ STI)

Write a Review | 5 Q&As
Part # IAG-ENG-1452
$5,939.99

Product will ship from manufacturer, average time to ship: 23 business days
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Features & Product Details

RallySport Direct carries the highly sought-after high-performance upgrades and accessories brought to you by IAG Performance. They build some of the best and most reliable engines for your Subaru! Perfect for your crazy race car build, rally car build, daily driver or off-road machine!

On this page, you are looking at the IAG Performance Stage 4 Tuff EJ25 Subaru Closed Deck Short Block. This is a carefully blueprinted and assembled racing engine block designed to handle the perils of increased power and torque output. This is a brand-new engine with new Subaru 2.5L case halves with all the right guts machined and assembled with a Haas VF-4SS mill to accept the IAG Closed Deck inserts. Additionally, the short block has been machined to fit 14mm head studs. The final finish to this block is machining for IAG Fire-Lock head gaskets, a revolutionary step in Subaru performance. These utilize an alloy ring at the top surface of the deck around the cylinder along with a special composite head gasket for high boost applications. 

Here are the details:

  • Brand new Subaru OEM case halves converted to Closed Deck 
  • IAG Fire-Lock receiver groove machining
  • Bored and honed to 99.75mm
  • IAG-Spec JE FSR 99.75mm 2618 Forged Pistons
  • .250" / .927" H13 Performance wrist pins, clips
  • IAG Spec Tri-Beam +2mm connecting rods
  • ARP625+ Rod bolts
  • ACL Rod and Main Bearings
  • Standard new Subaru Nitride Treated 2017+ STI crankshaft
  • Standard FHI Subaru case bolts/main bolts
  • Machined to accept 14mm head studs (head studs sold separately)
  • Requires IAG Fire-Lock Head Gaskets
  • Note: Compression ratio is subject to change based on cylinder heads. 

  • 8.2:1 on B, V, and W cylinder heads (EJ257)
  • 8.5:1 on D cylinder heads (EJ255)
  • Specifications

    Brand: IAG Performance
    Assembly: Assembled
    Bore Size (mm): 99.75
    Compression Ratio: 8.2:1
    Crank: OEM Forged
    Crank Size: OEM
    Displacement: 2.5L
    Piston Material: Forged Aluminum
    Power Output Rating (BHP): 1000
    Rods: Forged
    Mfgr. Warranty: 12 Months / 12k Miles
    Condition: New Product
    Return Policy:
    Standard

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    QUESTIONS & ANSWERS

    • Q: Shipping cost   Mkenya mark9 months ago

      I have seen on the page that its free shipping,please confirm is it free upto nairobi kenya
      • 0 of 0 people found the following answer helpful

        A:  This does qualify for free standard shipping inside of the US. For international shipments it would be subject to the shippers rates. You can enter your zip code in the cart for an estimated shipping charge.

        Lane H. @ RallySport Direct 8 months ago  
          
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    • Q: IAG Stage 4 tuff ej25  iheartsubarus20x025741 year ago

      What is the recommended break in period for this setup?
      • 0 of 0 people found the following answer helpful

        A:  IAG will include their recommended break-in procedure with their documentation. It is too long for this Q&A section.

        Lane H. @ RallySport Direct 11 months ago  
          
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    • Q: Horsepower  tutland1 year ago

      How much horsepower is this assembly rated for?
      • 0 of 0 people found the following answer helpful

        A: 

          
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      • 0 of 0 people found the following answer helpful

        A:  "Power Output Rating (BHP): 1000"

        R Car
          
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    • Q: Block material   Ottobot2 years ago

      I’m wondering if this upgraded block is forged as well because in the past I’ve experienced that OEM block is soft and any thread in the block gets stripped and have to be helicoiled to repair.
      • 0 of 0 people found the following answer helpful

        A:  The case halves are OEM Subaru parts that are converted to closed deck and tapped for larger head studs in-house by IAG.

        Marcus E. @ RallySport Direct 2 years ago  
          
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