IAG 2.5L Stage 2 Short Block 2006-2014 WRX, 2004+ STI

  • The IAG Stage 2 Short Block is designed for modified EJ25 Subarus that need a beefed-up performance short block. The IAG Stage 2 short block builds off the Stage 1's strengths by adding ACL Race bearings and IAG Spec H-Beam forged connecting rods. The upgraded rods and bearings are able to support additional engine load produced by larger turbochargers that the OEM STI rods cannot support reliably. Each IAG Stage 2 Short Block starts with new Subaru 2.5L 99.5mm stock bore EJ25 engine case halves as standard. The short block is measured and assembled using a new 2017+ Subaru 2.5L nitride treated STI crankshaft that is matched to ACL or King race main bearings. IAG-Spec H-Beam rods and ARP2000 rod bolts are utilized along with ACL or King race rod bearings. The case halves are sealed with new OEM main case bolts and sealant. Finally, Manley 99.5mm Platinum Series Forged Pistons are spec'd and installed finishing off the short block. 

    The IAG Stage 2 Short Block has a power output rating of 650BHP.

    Stage 2 Short Block Includes:
    • Case Halves - Brand new Subaru OEM case halves 99.5mm stock bore
    • Pistons - Manley 99.5mm Platinum Forged Pistons, Ringset, .210" Steel Pins, Clips, (Coated Skirts and Offset Wrist Pin)
    • Connecting Rods - IAG-Spec H-Beam Rods with ARP2000 rod bolts
    • Rod / Main Bearings - ACL or King Race Bearings
    • Crankshaft - Standard New Subaru Nitride Treated 2017+ STI Crankshaft
    • Case / Main Bolts - Standard FHI Subaru case bolts


    Additional Options Available:
    Hardware / Seals - OEM cover and seal kit - $105.99 

    *All IAG Short Blocks are balanced and blueprinted. 

    Compression Ratio: 8.5:1 on D Cylinder Heads (EJ255) 
    Compression Ratio: 8.2:1 on B, V and W EJ257 Heads with standard thickness gasket.

    For local pickup only; sorry, no mail-order.

  • SKU#: 10575STG2

    Shipping Weight: 100.0 lb

    Manufacturer: IAG

    Category: Engine Internals