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**This is considered a special order item and is not eligible for return to Reese Tuning. You can find the manufacturers warranty information linked below**
Typical lead time for these short blocks is between 4-8 weeks. Contact us for current lead time.
The IAG 750 Short Block is designed to solve the majority of common problems which plague modified EJ25 engines, especially at higher horsepower levels. The IAG 750 short block builds off our IAG 550 block's strengths by adding our proprietary closed deck system. This system strengthens and supports the cylinder walls to prevent cracks which can occur with increased cylinder pressures. (This is the most common issue when increasing horsepower.) The IAG 750 also features 99.75mm JE Forged Pistons and IAG Spec H beam connecting rods, along with ACL or King Race bearings. These components also significantly strengthen the common failure points such as cracked ring lands and spun bearings.
The IAG 750 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 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.
Our unique closed deck system significantly increases the strength of the OEM case halves. This process supports the cylinder walls at the top of the case in order to prevent flexing and possible cracking where the case bolt reliefs are cut into the back of the cylinder wall.
During the installation process we machine the assembled case halves in our Haas VF-4SS CNC mill to accept the IAG Closed Deck inserts. Once the case has been machined we heat it in an oven while freezing the specially machined inserts with liquid nitrogen. The inserts are then pressed into place and then machined to a mirror finish.
The unique inserts feature small passages that allow needed coolant flow to the deck surface. This means that the closed deck system does not affect the block's cooling ability and will not cause overheating, even in daily drivers.
Each IAG 750 Short Block features IAG Spec JE FSR 99.75mm Forged Pistons. These 2618 T6 Alloy high-strength pistons have been specifically designed to support increased cylinder pressures which come with more boost. FSR forgings reduce mass and wear caused by friction without sacrificing strength. This is accomplished by using an asymmetrical skirt design instead of the traditional full-round skirt, also this reduces weight significantly. Featuring smooth flowing radii on the domes and dishes, the design promotes excellent flame travel. The pistons are secured to the rods with .905 x 2.250" x .210" wall 9310 steel wrist pins with Tru Arc locks. The thicker steel wrist pins support additional power over the standard .180" pins.
If you plan to use the IAG 750 Short Block with EJ20 Cylinder Heads, make sure to select the "Hybrid Pistons" option at checkout. These specially designed JE pistons allow the use of EJ20 cylinder heads without the requirement for a chamber matching service to be performed to the cylinder heads. This option is great for international clients who are not able to send their cylinder heads in for modification. This also works great for USDM EJ20 owners who prefer to use 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.
Fitments:
2005-2006 Saab 9-2X Aero 2004-2013 Forester XT
2004-2006 Subaru Baja Turbo 2009-2010 Subaru Impreza 2.5 GT
2005-2009 Subaru Legacy GT 2002-2014 Subaru WRX
2005-2009 Subaru Outback XT 2004-2021 Subaru STI
Compression Ratio:
