IAG Stage 2.5 EJ25 Subaru Closed Deck Short Block

The IAG Performance Stage 2.5 International Hybrid EJ25 Subaru Closed Deck Short Block is engineered to enhance the performance of vehicles originally equipped with EJ20 2.0L engines by increasing displacement and low-end torque. This hybrid block utilizes custom-designed pistons that lower compression to seamlessly match EJ20 cylinder heads, eliminating the need for cylinder head chamber modifications. The product offers increased performance capabilities and improved reliability. Construction begins with brand new Subaru 2.5L engine case halves, which are then machined and converted to a closed deck configuration using IAG's proprietary inserts, creating a solid deck design with passages for essential coolant flow. The block is subsequently deck plate bored and honed to 99.75mm using a Sunnen SV-30 hone, allowing for custom piston-to-wall clearances tailored to specific needs. The assembled short block features a new 2017+ Subaru 2.5L nitride-treated STI crankshaft paired with ACL or King Race main bearings. IAG-Spec Tuff H-Beam connecting rods with ARP2000 rod bolts and ACL or King Race rod bearings are utilized. The case halves are secured with new OEM main/case bolts and sealant. Key components include IAG-Spec JE FSR 99.75mm 2618 forged pistons with Perfect Skirt Coating and offset wrist pins, .210" steel wrist pins, and clips. The block is a closed deck conversion using brand new Subaru OEM case halves, bored and honed to 99.75mm, with IAG-Spec Tuff H-Beam rods and ARP2000 rod bolts. It uses ACL or King Race bearings and a standard new Subaru nitride-treated 2017+ STI crankshaft. Standard FHI Subaru case bolts are included. A critical note for installation is that this short block must be used with EJ20 cylinder heads. The package includes one complete IAG short block. Installation instructions, warranty information, and break-in documentation are provided. IAG offers a one-year/12,000-mile warranty on this product.