IAG 750 EJ25 Subaru Closed Deck Short Block

The IAG Performance 750 EJ25 Subaru Closed Deck Short Block is designed to address prevalent problems in modified EJ25 engines, especially those experiencing high horsepower. By integrating IAG's proprietary closed deck system, this short block significantly reinforces cylinder walls, mitigating the risk of cracks that can arise from elevated cylinder pressures – a common failure point in performance applications. Constructed entirely from new components, the process begins with brand-new Subaru 2.5L engine case halves. These are precisely machined in-house using Haas VF-4SS CNC mills to accommodate IAG Closed Deck inserts, effectively transforming the block into a solid deck design. Following this, deck plates are attached, and the block is bored and honed to 99.75mm with a Sunnen SV-30 computer-controlled cylinder hone. This meticulous in-house process allows for custom piston-to-wall clearances, ensuring quiet operation and reduced oil consumption. The strengthened case halves are then assembled with a new 2017+ Subaru 2.5L nitride-treated STI crankshaft and IAG-Spec Tuff H-Beam connecting rods featuring ARP2000 rod bolts. High-performance ACL or King Race rod and main bearings are utilized, and all assemblies are balanced and blueprinted for optimal performance and longevity. The final assembly is sealed with new OEM main/case bolts and sealant. Each IAG 750 Short Block comes equipped with IAG-Spec JE FSR 99.75mm Forged Pistons, crafted from 2618 T6 Alloy for superior strength under high boost conditions. These pistons feature an asymmetrical skirt design for reduced weight and wear, along with robust .905 x 2.250" x .210" wall 9310 steel wrist pins. An optional "Hybrid" piston set is available for those planning to use EJ20 Cylinder Heads, simplifying installation by eliminating the need for chamber matching services on the heads. The block has a power output rating of 750 BHP. It is compatible with 2002-2021 Subaru and Saab models.