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IAG Performance 950 Series EJ25 Long Block w/ IAG 950 Heads 2002-2014 WRX / 2004-2021 STI / 2004-2013 Forester XT / 2005-2009 Legacy GT

$13,899.99
Original price $13,899.99 - Original price $14,299.99
Original price $13,899.99
$13,899.99 - $14,299.99
Current price $13,899.99
Stock Status: Ships Directly From Manufacturer – Delivery Times Vary What does this mean
Stock Status: Ships Directly From Manufacturer – Delivery Times Vary What does this mean
Stock Status: Ships Directly From Manufacturer – Delivery Times Vary What does this mean
Stock Status: Ships Directly From Manufacturer – Delivery Times Vary What does this mean
Stock Status: Ships Directly From Manufacturer – Delivery Times Vary What does this mean
Stock Status: Ships Directly From Manufacturer – Delivery Times Vary What does this mean
Stock Status: Ships Directly From Manufacturer – Delivery Times Vary What does this mean
Stock Status: Ships Directly From Manufacturer – Delivery Times Vary What does this mean
Stock Status: Ships Directly From Manufacturer – Delivery Times Vary What does this mean
Stock Status: Ships Directly From Manufacturer – Delivery Times Vary What does this mean
SKU IAG-ENG-L955S

DETAILS

The IAG 950 package is ideal for clients looking for an engine package to support up to 950 BHP applications. The IAG 950 Long Block features our IAG 950 Closed Deck Short Block that utilizes a brand new EJ20 or EJ25 Subaru case that is converted to closed deck and is bored and honed to 92.5 or 99.75mm. The IAG 950 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 EJ20 or EJ25 turbocharged engine. The IAG 950 internals include 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 IAG 950 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, IAG Beehive Springs, as well as GSC Billet Stage 2 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.

BUILT WITH 100% NEW COMPONENTS
The IAG 950 Short Block starts with brand new Subaru 2.5L engine case halves. Our machinists machine the assembled case halves in our Haas VF-4SS CNC mill to accept the IAG Closed Deck inserts, transforming the block into a solid deck. Next, a deck pair of deck plates are attached and the short block is bored and honed to 99.75mm in our in-house Sunnen SV-30 computer controlled cylinder hone. IAG's in-house honing process allows us to set custom piston to wall clearances to ensure quiet operation and reduced oil consumption. The Haas mill also cuts a groove at the top of each cylinder to accept the Fire-Lock™ head gasket rings and drills each head bolt hole for 14mm head studs. The modified case halves are then assembled using a new 2017+ Subaru 2.5L nitride treated STI crankshaft and IAG-Spec Tuff H-Beam connecting rods with ARP rod bolts. IAG Short blocks feature ACL or King Race rod and main bearings and are all balanced and blueprinted. Finally, the case halves are sealed with new OEM main/case bolts and sealant.

NEVER WORRY ABOUT HEAD GASKET FAILURES
The IAG 950 EJ25 Closed Deck Short Block features our propietary "Fire-Lock™" Head gasket system. This system has been proven in our record setting race cars to be the strongest Subaru head gasket system ever produced. To achieve these results our engineers separated the combustion chamber sealing from the fluid sealing aspects of the head gaskets. Our machinists carefully machine a lip at the top of each cylinder to accept the "Fire-Lock™" ring. With the ring locked in place, it stands proud above the deck, providing a superior seal. The separate gasket bodies take care of sealing oil and coolant passges and keeping them out of the combustion chamber. 14mm Head studs (Not Included) hold the assembly together.

CLOSED DECK FOR EXTRA STRENGTH
Improve your engine's strength with our closed deck system, specially designed to prevent flexing and cracking in the cylinder walls. Our Haas VF-4SS CNC mill expertly machines and precisely fits the IAG Closed Deck inserts into the case for a seamless, mirror finish. The inserts also allow for proper coolant flow, ensuring no overheating, even for daily drivers. Elevate your driving experience with IAG Performance's 950 Series EJ25 Long Block.

PISTONS SPECIALLY DESIGNED WITH POWER IN MIND
The pistons used in the IAG 950 Short Blocks are specifically designed to support the rigors of racing. Designed in partnership with JE, these IAG-Spec pistons feature electroless nickel plating and a 2618 Alloy. Extra thick ring lands resist collapsing under pressure. The upgraded .250" wall H13 tool steel offset wrist pins are designed to hold up to 950 BHP without bending or breaking. The pistons also feature JE's Perfect Skirt coating.

BUILT WITH RACING IN MIND
The IAG 950 CNC Ported Race Cylinder Heads are designed for racing and competition. These fully CNC ported heads provide a significant upgrade in flow over the IAG 750 heads. These heads work great for cars where getting more power might be the difference between winning or losing that big race. The IAG 950 heads work great for drag racing, as well as high horsepower time attack or hill climb, and are designed to support up to 950 BHP with supporting mods. These heads include upgraded GSC +1MM Superalloy Valves, GSC Viton Valve Stem Seals, Upgraded GSC Valve Guides, IAG-Spec Beehive Valve Springs with Titanium Retainers, and OEM Keepers. GSC S2 Camshafts are available with OEM valve lifter buckets. We also offer an optional chamber modification service (see below) for EJ20 heads to allow use on EJ25 short blocks.

BUILT WITH 100% NEW COMPONENTS
This IAG 950 fully CNC ported head package starts with brand new WRX STI OEM head castings directly from Subaru of America. The bare castings are visually inspected then fixtured into our in-house Centroid 5-axis CNC Machine. The Centroid CNC ports the intake and hard to reach exhaust "dog-leg" port runner. The benefit of CNC porting is not only an efficient way of machining the heads it also offers consistent port results that are hard to achieve by hand. Once the Centroid completes the port process the heads undergo a cam clearance machining process that removes material from the lifter area where large duration cam profiles are known to contact the castings. Shortly after the heads are drilled to fit larger 1/2" or 14mm head studs, which are commonly used in high horsepower builds. Next, the OEM guides are pressed out and replaced in favor of GSC Manganese-Bronze valve guides that are shaped to improve airflow. Once all the new intake and exhaust guides are in place they are diamond-honed in our honing station. The heads are then fixtured in our Newen 3.0 Valve Guide and Seat Machine to cut all intake and exhaust seats with a multi-angle valve job that suits the flow characteristics of GSC's +1mm valves. At this point, the heads' decks are resurfaced using our TS-3000 BlockMate which cuts the aluminum to a smooth even finish. Next, the heads are ultrasonically cleaned to remove debris and oils from the machining process. Finally, the heads are reassembled using IAG-Spec Beehive Valve Springs and Retainers along with GSC Viton stem seals.

IAG 950 Closed Deck EJ25 Short Block:

  • 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 - *Head studs are sold separately
  • 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.

IAG 950 EJ20 2.0L Closed Deck Short Block:

  • Case Halves -Converted to Closed Deck using brand new Subaru OEM case halves, bored and honed to 92.5mm.
  • 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 - *Head studs are sold separately
  • Pistons -IAG-Spec JE FSR 92.5mm 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 EJ20 Crankshaft.
  • Case / Main Bolts -Standard FHI Subaru case bolts.


IAG 950 CNC Ported Cylinder 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 - IAG-Spec Beehive Valve Springs & Retainers
  • Guides - GSC Maganese Valve Guides
  • Valve Seals - GSC Valve Stem Seals
  • Lifters - OEM Lifter Buckets
  • Camshafts - GSC Stage 2 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 Rating: The IAG 950 Long Block has a power output rating of 950 BHP.

IAG stands behind every hand-built engine they produce. IAG's Standard Long Block Workmanship Warranty covers your long block for 12 months or 12,000 miles. IAG has also teamed up with a selection of IAG Certified Installation Facilities which offer up to a 24-month/24,000-mile workmanship warranty when the engine is purchased, installed, and tuned by that IAG Certified Installer.

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