Using the same world-leading technology found in Willall’s incredible billet GT-R block, the billet 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. The Stage “X” Block is a complete short block built on the Willall 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 Short Block Includes:
- Case - WREJBB 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)
- Pistons – IAG-Spec JE FSR 99.75mm 2618 Forged Pistons, Electro-nickel Plated Tops & Ring area, Ringset, .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 Billet Crank by Callies
- Case / Main Bolts – ARP Main Bolts
- *IAG Fire-Lock .051" Head Gaskets with IAG-Spec Alloy Ring Set* (PN# IAG-ENG-1740)
- 14mm Head Studs
- 8.5:1 on D Cylinder Heads (EJ255)
- 8.2:1 on B, V and W EJ257 Heads with standard thickness gasket.
Power: The IAG / Willall Stage X Short Block has a power output rating of 1100+BHP.
*All IAG short blocks are balanced and blueprinted.
These blocks are built to order and have a lead time of 2-4 weeks. Free shipping includes the 48 continental states only and will be shipped in a reinforced triple wall cardboard box. We are an authorized IAG dealer and an OEM Subaru parts dealership.