IAG 900 Closed Deck 2.5L Long Block Engine w/ Stage 4 Heads – Subaru WRX/STI/FXT/LGT (EJ25)


IAG 900 Closed Deck 2.5L Long Block Engine w/ Stage 4 Heads – Subaru WRX/STI/FXT/LGT (EJ25)

Warranty: Years

Availability: In Stock
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Subaru Doctor Parts

Vendor: Paul
Gold Coast Queensland 4215

The IAG Performance Hand-Built Subaru EJ25 Closed Deck Long Block Engine Packages are a complete, valve cover to valve cover, crate engine. These engines offer significant ease of installation for customers seeking a complete “drop-in”? engine package for their WRX, STI, Forester XT or Legacy GT. The Long Blocks feature a combination of our proven IAG Performance Closed Deck Short Block and Cylinder Head packages, along with other race-proven components to complete the assembly. When paired with our Long Block Installation Packages, you 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.

The IAG 900 package is ideal for clients looking for an engine package to support up to 900 BHP applications. The IAG 900 Long Block features our Magnum Closed Deck Short Block that utilizes a brand new EJ25 Subaru case that is converted to closed deck and is bored and honed to 99.75mm. The Magnum block features 14mm head stud machining, as well as our Fire-Lock gasket solution that is loosely derived from diesel technology where a counterbore step is machined around each cylinder bore allowing specially sized fire rings to drop into the machined area and head gasket bores. The combination of the alloy compression shims and gaskets assure maximum sealing for a Subaru EJ25 turbocharged engine. The Magnum internals includes IAG-Spec JE FSR 2618 forged pistons, .250″ / .906″ H13 pins, IAG-Spec Tuff H-Beam +2mm connecting rods with ARP 625+ rods bolts and an OEM STI crankshaft. The block is then paired up with our Stage 4 Fully CNC Ported Cylinder Heads to deliver maximum flow for high horsepower applications. The heads start as brand new Subaru OEM cylinder head castings that are CNC machined and resurfaced. The heads are outfitted with GSC valve train components, consisting of +1mm oversized intake and SuperAlloy exhaust valves, Beehive Springs as well as your choice of GSC Billet Stage 2 or Stage 3 camshafts. To complete the package, we add an IAG / ARP 14mm head stud set and all the required gaskets for the final valve cover-to-valve cover assembly.

IAG’s Break-in Instructions MUST be followed, and the long block must be professionally installed for the 12 month/12,000 mile workmanship warranty to be applicable. If the previous engine experienced an internal failure then all oiling components (i.e. cooler, pump, pickup, cam gears, and solenoids, etc) as well as other necessary components as per your installer’s recommendations, must be replaced during installation.

IAG 900 Long Block Engine Includes:

Stage Magnum Closed Deck Short Block Includes:

Case Halves -?Converted to Closed Deck using brand new Subaru OEM case halves, bored and honed to 99.75mm.
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 -?Machine Case for 14mm head studs
Pistons -?IAG-Spec JE FSR 99.75mm 2618 Forged Pistons, Electroless Nickel Plated Tops & Ring area, Ring Set, .250″ / .906″ H13 Wrist Pins, Clips, (Perfect Skirt Coating and Offset Wrist Pins)
Connecting Rods -?IAG-Spec Tuff H-Beam +2mm / ARP 625+ 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.

Stage 4 Heads:

Heads -?Brand New Subaru OEM WRX STI Cylinder Head Castings
Machine Porting -?CNC Ported Intake and Exhaust Runners
Intake Valves -?GSC 37mm (+1mm) Intake Valves
Exhaust Valves -?GSC 33mm (+1mm) SuperAlloy Exhaust Valves
Springs / Retainers -?GSC Beehive Valve Springs & Retainers
Guides -?GSC Maganese Valve Guides
Valve Seals -?GSC Valve Stem Seals
Lifters -?OEM Lifter Buckets
Camshafts -?GSC Stage 2 or Stage 3 Billet Camshafts
Multi-Angle Valve Job
Machined Cam Lobe Clearance
Drilled For 14mm Heads Studs
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

*All IAG short blocks are balanced and blueprinted.

Power:?The IAG 900 Long Block has a power output rating of 900BHP.

Additional Options:

IAG sells separately a Long Block Basic Installation Kit that provides all of the basic components needed to install one of our EJ25 Long Block Engine Packages in one complete kit. All fluids for initial break-in are included.

Vehicle Fitment:

Please confirm correct heads required by checking the casting and select appropriate package from the dropdown box. The following list is provided as a rough guide only and may not suit your engine specifically.?No returns/exchanges will be accepted if the incorrect heads are purchased:

2006-2007 Subaru WRX (D25 Heads)
2008-2014 Subaru WRX (D25 Heads)
2006-2007 Subrau STI (V25 Heads)
2008-2014 Subaru STI (W25 Heads)
2015-2021 Subaru STI (W25 Heads)
2003-2005 Subaru Forester XT (V25 Heads)
2005-2008 Subaru Forester XT (V25 Heads)
2008-2013 Subaru Forester XT (D25 Heads)
2007-2009 Subaru Liberty GT (D25 Heads)

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Product Location

3 Jay Gee Ct, Nerang QLD 4211, Australia

We are an authorised distributor for all brands and any manufacturer warranty is passed onto the original purchaser of any product. We will also discuss warranty/returns with the supplier making the whole process as smooth and easy as possible. Unfortunately we are not able to warrant any items that we deem to have been misused, altered, abused or not used for their intended purpose. It is the responsibility of the purchaser to verify the part prior to installation and it’s installed correctly. Once it has been used, we cannot offer a return.

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