The IAG Performance hand-built Subaru 1150 2.35L Destroked Long Block Engine package is a complete, valve cover to valve cover, crate engine. This engine provides a straightforward "drop-in" solution for those looking to upgrade their 2018-2021 Subaru STI. This long block features a combination of our proven IAG EJ25 2.35L Destroked Closed Deck Short Block and IAG 1150 Cylinder Head packages, along with a full range of carefully selected high-performance components to complete the assembly. When paired with our Long Block Installation Packages, you’ll have a true plug-and-play solution to get you back on the road, FAST! All components included are BRAND NEW and there is NEVER A CORE CHARGE required. With custom IAG Spec +2mm Tri-beam forged connecting rods and IAG Spec billet 75mm crankshaft, IAG’s Destroked Long Block decreases piston speed, optimizing the rod-to-stroke ratio. This adjustment enhances key engine dynamics such as aspiration and combustion efficiency, while minimizing component wear. In terms of performance, this means increased power output, extended ring life, and the ability to rev higher—making this long block an ideal choice for track days, racing, or competition drag racing applications.

IAG 1150 2.35L Destroked Long Block Includes: IAG 1150 EJ25 2.35L Short Block: Case Halves -Brand new Subaru OEM case halves, Pinned Mains - Machine case for 9.5mm pinned mains and lined honed, 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, Head Studs - Machined for 14mm Head Studs, Pistons -JE 99.75mm FSR 2618 Custom Pistons and .240" H13 Tool Steel Wrist Pins with JE Pro Seal Ring Set, Connecting Rods -Custom IAG Spec +2mm Tri-Beam Forged Connecting Rods with ARP 625+ Rod Bolts, Rod / Main Bearings -ACL Race Bearings, Crank -IAG Spec Billet 75mm Crankshaft, Case / Main Bolts - ARP Main Bolts. IAG 1150 Fully CNC Ported Cylinder Heads: Heads - Brand New Subaru OEM WRX STI Cylinder Head Castings, Machine Porting - CNC Ported Intake and Exhaust Runners, Intake Valves - Ferrea 37mm (+1mm) Comp Plus Intake Valves, Exhaust Valves - Ferrea 33mm (+1mm) Comp Plus Exhaust Valves, Springs / Retainers - Ferrea Dual Valve Springs & Titanium Retainers, Keepers - Ferrea Valve Keepers, Guides - GSC Manganese Bronze Valve Guides, Valve Seals - GSC Valve Stem Seals, Lifters - Kelford DLC Coated Lifter Buckets, Camshafts - GSC Stage 3 Billet Camshafts, Multi-Angle Valve Job, Machined Cam Lobe Clearance, Drilled For 14mm Heads Studs, Resurface, Ultrasonic Cleaning, Final Lash. Gaskets, Hardware & Accessories: Head Studs - IAG / ARP 14mm Set, Head Gaskets - IAG Fire-Lock™, Valve Cover Gaskets - OEM, Cam Seals - OEM, Valve Covers - OEM, Wrist Pin Seal, Rear Main Seal & Separator Kit, Crankshaft Woodruff Key.
,Power: The IAG 1150 Long Block has a power output rating of 1150BHP.
,All IAG short blocks are balanced and blueprinted.