IAG Performance Stage X Short Block 2002-2014 WRX / 2004-2021 STI
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
- 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.