IAG 950 EJ25 Subaru Short Block - Subaru Models (Inc. 2002-2014 Subaru WRX / 2004-2021 STI / 2004-2013 Forester)

Please Note: This item is not eligible for standard ground shipping and must be delivered via freight. To receive a custom invoice that includes all applicable freight charges, kindly contact us by email or phone.

 

 

RACING ON SUNDAY, WORKING ON MONDAY

The IAG 950 Short Block stands as the ultimate "weekend warrior" engine block, engineered to handle up to 950 BHP, making it our toughest offering for street applications. Featuring +2mm IAG Spec H-Beam forged connecting rods, IAG-Spec JE Pistons with electroless nickel plated coating and H13 tool steel wrist pins, alongside our renowned "Fire-Lock™" head gasket system for 14mm head studs, each IAG 950 short block undergoes meticulous hand assembly using ACL or King rod and main bearings. This combination of premium components ensures that the IAG 950 Short Block is perfectly suited for both drag and road racing endeavors.

 

CRAFTED FROM 100% NEW COMPONENTS

The foundation of the IAG 950 Short Block begins with pristine Subaru 2.5L engine case halves. Our skilled machinists meticulously process the assembled case halves using our Haas VF-4SS CNC mill to accommodate the IAG Closed Deck inserts, effectively transforming the block into a solid deck. Following this, a set of deck plates is attached, and the short block undergoes precision boring and honing to a diameter of 99.75mm in our in-house Sunnen SV-30 computer-controlled cylinder hone. Leveraging IAG's in-house honing process, we customize piston-to-wall clearances to ensure smooth operation and minimize oil consumption. Additionally, the Haas mill precisely cuts a groove at the top of each cylinder to accommodate the Fire-Lock™ head gasket rings and drills each head bolt hole for 14mm head studs. The modified case halves are then meticulously assembled using a new 2017+ Subaru 2.5L nitride-treated STI crankshaft and IAG-Spec Tuff H-Beam connecting rods with ARP rod bolts. Every IAG Short Block is equipped with ACL or King Race rod and main bearings, meticulously balanced and blueprinted. Finally, the case halves are securely sealed using new OEM main/case bolts and sealant, completing the meticulous crafting process.

 

ELIMINATE CONCERNS ABOUT HEAD GASKET ISSUES

With the IAG 950 EJ25 Closed Deck Short Block, you can say goodbye to worries about head gasket failures, thanks to our exclusive "Fire-Lock™" Head gasket system. This system, validated in our race cars setting records, represents the most robust Subaru head gasket system ever created. To achieve this unmatched reliability, our engineers ingeniously separated the sealing of the combustion chamber from that of the fluid passages in the head gaskets. Our skilled machinists meticulously create a lip at the top of each cylinder to accommodate the "Fire-Lock™" ring. Once the ring is securely in place, it protrudes above the deck, ensuring a superior seal. The separate gasket bodies effectively seal oil and coolant passages, preventing them from leaking into the combustion chamber. Completing the assembly, 14mm Head studs (Not Included) securely hold everything together, providing unparalleled peace of mind.

 

REINFORCED WITH CLOSED DECK TECHNOLOGY

Our innovative closed deck system significantly bolsters the strength of the OEM case halves. This method provides robust support to the cylinder walls at the top of the case, effectively preventing any flexing or potential cracking near the case bolt reliefs cut into the back of the cylinder wall. Throughout the installation procedure, we utilize our Haas VF-4SS CNC mill to machine the assembled case halves, ensuring precise accommodation of the IAG Closed Deck inserts. Following this, we employ a unique process involving heating the case in an oven while simultaneously freezing the specially machined inserts with liquid nitrogen. Once heated and frozen respectively, the inserts are meticulously pressed into place and then meticulously machined to achieve a flawless mirror finish. These distinctive inserts incorporate small passages to facilitate essential coolant flow to the deck surface. Consequently, the closed deck system maintains the block's cooling efficiency and effectively prevents any risk of overheating, even during everyday driving.

 

ENGINEERED PISTONS BUILT FOR POWER

The pistons employed in the IAG 950 Short Blocks are meticulously tailored to endure the rigorous demands of racing. Crafted in collaboration with JE, these specialized IAG-Spec pistons boast electroless nickel plating and are constructed from 2618 Alloy. Engineered with extra thick ring lands, they are fortified to withstand high pressure without collapsing. The upgraded .250" wall H13 tool steel offset wrist pins are specifically designed to endure forces up to 950 BHP without bending or breaking. Additionally, these pistons feature JE's Perfect Skirt coating for enhanced performance and longevity.

 

IAG 950 Closed Deck EJ25 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 - *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.

 

Compression Ratio:

• 8.5:1 on D Cylinder Heads (EJ255)
• 8.2:1 on B, V and W EJ257 Heads with standard thickness gasket.

 

Head Gasket Required:

• *IAG Fire-Lock™ .051" Head Gaskets with IAG-Spec Alloy Ring Set* PN# IAG-ENG-1740

 

IMPORTANT DELIVERY NOTE:

Your order is shipping Via Truck Freight which requires you to be available at the time of receipt. There is a possibility the trucking company will try to schedule a delivery time with you.

At the time of delivery, the driver will hand you the delivery receipt also referred to as the bill of lading, you will use this to notate any damages to the shipment. It is important that you fully inspect the shipment from all sides and notate any dents, punctures or rips in the outside packaging on the delivery receipt. Once you've inspected your shipment from the outside, you will need to open it and check the product in its entirety for damages and notate them if any.

If there is no damage sign for the package and enjoy!

In the rare case, you do find that your order arrived with damages, it is important you follow these steps.

- Do not refuse the product
- Document the damages in as much detail as possible on the Bill of Lading
- Take numerous photos from all angles (including packaging)
- Keep the product and contact the shipping company to start the damage claim
- Contact us either by phone or email for the next steps

In the situation where the delivery driver is unable to wait for you to open and inspect your product, simply document "driver was unable to wait for inspection." All damage must be noted on the Bill of Lading before signing and initiating a damage claim. If the damage is not notated before signing for the item it is assumed to be in good condition. This will forfeit the ability for a shipping claim and you will not be eligible for refund or replacement.