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IAG Performance / Willall Stage X 2.5L Subaru Billet Aluminum Short Block For WRX, STI, LGT, FXT

$14,999.99
IAG-ENG-1611

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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 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

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.

*All IAG short blocks are balanced and blueprinted.

Not planning on reusing your original short block service plugs and covers? IAG offers a simple comprehensive cover and seal kit that includes (1) Rear main seal, (3) OEM wrist pin plugs, (3) OEM wrist pin plug washers, (1) OEM separator cover, (6) OEM separator cover bolts, (1) OEM wrist pin service cover, (1) OEM wrist pin service cover O-ring and (2) OEM wrist pin service cover screws. *If you are reusing your original wrist pin service plugs and covers always replace the (3) OEM wrist pin plug washers and (1) wrist pin service cover O-ring before installing a short block to avoid potential leaks. *Never reuse a rear main seal on a new short block.

Model Year & Fitment

2002-2005 Subaru WRX (Requires Mods)

2006-2014 Subaru WRX

2004-2018 Subaru STI

2005-2009 Subaru Legacy GT

2004-2013 Subaru Forester XT

This product can expose you to chemicals including Lead, which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov

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