IAG Performance / Willall Stage X 2.5L Subaru Billet Aluminum Short Block For Wrx, Sti, Lgt, Fxt

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