IAG Stage 4 Tuff EJ25 Subaru Closed Deck Short Block - Subaru Models (inc. 2006-2014 WRX / 2004+ STI)

Spectral Performance carries the highly sought-after high-performance upgrades and accessories brought to you by IAG Performance. They build some of the best and most reliable engines for your Subaru! Perfect for your crazy race car build, rally car build, daily driver or off-road machine!

This is the IAG Performance Stage 4 Tuff EJ25 Subaru Closed Deck Short Block. This is a carefully blueprinted and assembled racing engine block designed to handle the perils of increased power and torque output. This is a brand-new engine with new Subaru 2.5L case halves with all the right guts machined and assembled with a Haas VF-4SS mill to accept the IAG Closed Deck inserts. Additionally, the short block has been machined to fit 14mm head studs. The final finish to this block is machining for IAG Fire-Lock head gaskets, a revolutionary step in Subaru performance. These utilize an alloy ring at the top surface of the deck around the cylinder along with a special composite head gasket for high boost applications. 

HIGHLIGHTS:

• Brand new Subaru OEM case halves converted to Closed Deck 
• IAG Fire-Lock receiver groove machining
• Bored and honed to 99.75mm
• IAG-Spec JE FSR 99.75mm 2618 Forged Pistons
• .250" / .927" H13 Performance wrist pins, clips
• IAG Spec Tri-Beam +2mm connecting rods
• ARP625+ Rod bolts
• ACL Rod and Main Bearings
• Standard new Subaru Nitride Treated 2017+ STI crankshaft
• Standard FHI Subaru case bolts/main bolts
• Machined to accept 14mm head studs (head studs sold separately)
• Requires IAG Fire-Lock Head Gaskets

NOTE: COMPRESSION RATIO IS SUBJECT TO CHANGE BASED ON CYLINDER HEADS 

• 8.2:1 on B, V, and W cylinder heads (EJ257)
• 8.5:1 on D cylinder heads (EJ255)