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.