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IAG Performance

Crest CNC Stage X 2.5L Subaru Billet Aluminum Short Block

Fits: 02-14 WRX, 04-21 STi, 05-12 LGT, 04-13 FXT

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IAG Performance Crest CNC Stage X 2.5L Subaru Billet Aluminum Short Block
Fits: 02-14 WRX, 04-21 STi, 05-12 LGT, 04-13 FXT
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Fitment

  • 2004–2013 Subaru | Forester XT
  • 2002–2021 Subaru | WRX
  • 2004–2021 Subaru | WRX STI
  • 2005–2012 Subaru | Legacy GT

Description

The CNC Billet Aluminum EJ case seeks to change the Subaru performance tuning market by reinventing the EJ and addressing virtually every weakness that exists in max-power builds.

Each IAG / Crest CNC Case is machined from 6061-T6 Aerospace Aluminum and features Darton Ductile Iron Sleeves. The block is designed with increased material thickness over the OEM cast aluminum case halves and adds a unique 4-bolt bottom end for additional strength.

The IAG / Crest CNC Stage “X” Block, (Formally Willall) is a complete short block built on the Crest billet platform, which also includes pistons, rods, bearings, crank, bore/hone, case bolts, line hone, and final assembly and blueprinting.

Stage X Billet EJ25 Case Features:

  • Machined from solid billet 6061-T6 Aerospace grade aluminum
  • Darton Ductile iron sleeves
  • Increased material thickness in all known weak points (around head studs, bottom end location)
  • Unique 4 bolt bottom end strengthening
  • Threads are rolled into the block rather than conventionally cut for much greater strength
  • Full cooling system operation
  • Radiused coolant and oil galleries for improved flow and less foaming/turbulence
  • Fits all factory engine bay ancillaries (i.e. AC/PS/etc.)
  • Multiple Times stiffer and stronger than the stock case
  • Precision machined for a superior surface finish
  • Hard anodized to avoid marking or straining

IAG Stage X Complete Shortblock Includes:

  • Case -Crest Billet / Sleeved Case Halves
  • Fire-Lock™ -IAG Fire-Lock™ receiver groove machining, latest solution to prevent head gasket failure on high horsepower and high boost Subaru's - *IAG Fire-Lock™ head gaskets required
  • Machining -Machined for 14mm Head Studs *(Studs sold separately / Note the proper head gaskets or head gasket modifications are required for proper fitment with 14mm studs.
  • Pistons -IAG-Spec JE FSR 99.75mm 2618 Forged Pistons, Electro-nickel Plated Tops & Ring area, Ring Set, .250" / .927" H13 Wrist Pins, Clips, (Perfect Skirt Coating and Offset Wrist Pins)
  • Connecting Rods -IAG-Spec +2mm Tri-Beam w/ ARP625+ Rod Bolts
  • Rod/Main Bearings -ACL/King Race Bearings
  • Crankshaft -IAG-Spec Billet Crank
  • Case / Main Bolts -ARP Main Bolts

Additional Options Available:

  • Head Studs -IAG / ARP Spec 14mm head studs, nuts, and washers
  • Oil Pumps -IAG Stage 2 CNC Ported 11mm EJ Oil Pump or Subaru JDM 12mm Oil Pump
  • IAG Oil Pickup - Upgraded oil pickup featuring heavy gauge steel tubing, 2 point bracket & mesh filter
  • IAG Oil Baffle - Upgraded oil control baffle and windage tray
  • IAG Oil Pickup & Baffle Set - Upgraded oil pickup, oil control baffle, and windage tray
  • Hardware / Seal Option -(Includes: Wrist pin plugs, washers, separator cover, bolts, etc. In case you don't want to transfer from the original engine).

Required:

  • *IAG Fire-Lock™ .051" Head Gaskets with IAG-Spec Alloy Ring Set* PN# IAG-ENG-1740
  • 14mm Head Studs


Compression Ratio:

  • 8.5:1 on D Cylinder Heads (EJ255)
  • 8.2:1 on B, V and W EJ257 Heads with standard thickness gasket.


The IAG / Crest CNC Stage X Short Block has a power output rating of 1100+BHP.

*All IAG short blocks are balanced and blueprinted.


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