IAG Performance 750 Closed Deck Includes: Case Halves - Subaru Models (Inc. 2002-2021 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.

 

 

THE SOLUTION PROVIDER

Addressing the prevalent issues encountered in modified EJ25 engines, particularly at higher horsepower thresholds, the IAG 750 Short Block is engineered to resolve them effectively. Building upon the strengths of our IAG 550 block, the IAG 750 incorporates our exclusive closed deck system. This system reinforces and stabilizes the cylinder walls, mitigating the risk of cracks often induced by increased cylinder pressures—the primary concern when boosting horsepower. Additionally, the IAG 750 boasts 99.75mm JE Forged Pistons and IAG Spec H beam connecting rods, accompanied by ACL or King Race bearings. These components play a vital role in fortifying common failure points such as cracked ring lands and spun bearings, ensuring enhanced durability and reliability.

 

CONSTRUCTED WITH 100% NEW COMPONENTS

At the core of the IAG 750 Short Block lies brand-new 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, converting the block into a solid deck. Following this, a set of deck plates is affixed, and the short block undergoes precision boring and honing to a diameter of 99.75mm using our in-house Sunnen SV-30 computer-controlled cylinder hone. Leveraging IAG's proprietary honing process, we tailor piston-to-wall clearances to ensure smooth and quiet operation while minimizing oil consumption. The modified 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 ARP rod bolts. Every IAG Short Block is equipped with ACL or King Race rod and main bearings, meticulously balanced and blueprinted to exacting standards. Finally, the case halves are securely sealed using new OEM main/case bolts and sealant, completing the assembly process.

 

ENHANCED STRENGTH WITH CLOSED DECK

Our exclusive closed deck system significantly enhances the durability of the OEM case halves by reinforcing the cylinder walls at the top of the case. This crucial process prevents flexing and potential cracking, particularly in areas where the case bolt reliefs are cut into the back of the cylinder wall. During the installation phase, we meticulously machine the assembled case halves using our Haas VF-4SS CNC mill to accommodate the IAG Closed Deck inserts. Following machining, we heat the case in an oven while simultaneously freezing the specially machined inserts with liquid nitrogen. Subsequently, the inserts are carefully pressed into place and then machined to achieve a flawless mirror finish. These unique inserts incorporate small passages that facilitate essential coolant flow to the deck surface. As a result, the closed deck system seamlessly integrates with the block's cooling capability, ensuring optimal engine temperature regulation without the risk of overheating, even during daily driving scenarios.

 

ENGINEERED FOR BOOST: FORGED PISTONS

Found within every IAG 750 Short Block are IAG Spec JE FSR 99.75mm Forged Pistons. Crafted from 2618 T6 Alloy, these pistons are meticulously designed to withstand the heightened cylinder pressures accompanying increased boost levels. FSR forgings, known for their ability to reduce mass and wear caused by friction while preserving strength, are incorporated into these pistons. Utilizing an asymmetrical skirt design instead of the traditional full-round skirt significantly reduces weight without compromising durability. With smooth flowing radii on the domes and dishes, these pistons facilitate optimal flame travel. To ensure secure attachment to the rods, .905 x 2.250" x .210" wall 9310 steel wrist pins equipped with Tru Arc locks are utilized. The thicker steel wrist pins provide enhanced support for additional power compared to standard .180" pins.

 

ALTERNATIVE "HYBRID" PISTONS FOR EJ20 HEADS

For those intending to pair the IAG 750 Short Block with EJ20 Cylinder Heads, be sure to opt for the "Hybrid Pistons" selection during checkout. These specially engineered JE pistons are designed to facilitate the use of EJ20 cylinder heads without necessitating a chamber matching service on the cylinder heads. This option proves advantageous for international customers who cannot send their cylinder heads for modification. It also serves as an excellent choice for USDM EJ20 owners who prefer utilizing a 2.5L short block. The 9.5:1 Compression JE FSR piston set includes .905 x 2.250 straight wall carbon steel wrist pins with Tru Arc locks, along with a complete ring set.

 

IAG 750 Closed Deck Includes:

Case Halves -Converted to Closed Deck using brand new Subaru OEM case halves, bored and honed to 99.75mm.
Pistons -IAG-Spec JE FSR 99.75mm 2618 Forged Pistons, Ring Set, .210" 9310 Steel Wrist Pins, Clips, (Perfect Skirt Coating and Offset Wrist Pins)
Connecting Rods -IAG-Spec Tuff H-Beam / ARP2000 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:

9.5:1 on D Cylinder EJ255 Heads w/ OEM Head Gasket
8.9:1 on B, V and W EJ257 Heads w/ OEM Head Gasket
9.6:1 on S20 Heads without Combustion Chamber Mod and with OEM Head Gasket
9.1:1 on D Cylinder EJ255 Heads w/ .039" JE Proseal Head Gasket
8.6:1 on B, V and W EJ257 Heads w/ .039" JE Proseal Head Gasket
9.2:1 on S20 Heads without Combustion Chamber Mod and with .039" JE Proseal Head Gasket

 

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.