IAG Stage X EJ25 Billet Aluminum Short Block

Using the same world-leading technology found in Willalls 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 Shortblock 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 / 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 “ Manley Billet Crank
• Case / Main Bolts “ ARP Main Bolts

Additional Options Available

• Head Studs - IAG / ARP Spec 14mm head studs, nuts, and washers - $550
• Oil Pumps - Subaru JDM 12mm Oil Pump - $219 / OEM Subaru 11mm Oil Pump - $199.95
• Hardware / Seal Option - $105.99 (Includes: Wrist pin plugs, washers, separator cover, bolts, etc. In case you dont 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 / Willall Stage X Short Block has a power output rating of 1100+BHP.