IAG 1150 Series EJ25 Short Block 06-14 WRX / 04-21 STI / 04-13 Forester XT / 05-09 Legacy GT

IAG 1150 Series EJ25 Short Block 06-14 WRX / 04-21 STI / 04-13 Forester XT / 05-09 Legacy GT

The IAG 1150 Series short block is an EJ25 built for Subaru owners who drag race high-horsepower cars on a regular basis. It fits the 2006-2014 WRX, 2004-2021 STI, 2004-2013 Forester XT and 2005-2009 Legacy GT. IAG rates it at 1150 BHP and says it remains streetable, though its focus is the track.

Build details

• Case halves: Brand new OEM Subaru EJ25, converted to Stage 4 closed deck, bored and honed to 99.75mm with deck plates on a Sunnen SV-30
• Pinned mains: Case machined for 9.5mm pins and line honed; ARP main bolts
• Head sealing: Fire-Lock receiver groove machining; drilled and tapped for 14mm head studs
• Crankshaft: IAG-Spec billet, for added oiling and to limit main bearing distortion
• Connecting rods: IAG-Spec +2mm Tri-Beam with ARP 625+ rod bolts
• Pistons: IAG-Spec JE FSR 99.75mm 2618 forged, electroless nickel plated tops and ring area, .250" / .927" H13 wrist pins, clips, Perfect Skirt coating and offset wrist pins
• Piston details: 25% larger oil ring and gas ports to help ring sealing under high boost
• Bearings: ACL or King race bearings
• Components: 100% new parts

Before you order

IAG Fire-Lock .051" head gaskets with the IAG-Spec Alloy Ring Set (PN IAG-ENG-1740) are required. Compression is 8.5:1 on D heads (EJ255) and 8.2:1 on B, V and W EJ257 heads with a standard-thickness gasket. Send us your VIN or engine code and we will confirm fitment before you order.

See also: Subaru oil pickup tube problems · FA20 vs EJ25 · head studs vs head bolts · EJ257 problems · is it worth replacing an engine? · Subaru head gasket problems and ringland failure · signs of a blown head gasket · Subaru WRX and STI parts · EJ255 vs EJ257 · subaru ej25 / ej257 · IAG Performance Subaru blocks and all engines by engine code.

Shipping and returns

Shipping is a flat $80.00 per order to US addresses, and returns are free within 15 days of delivery. Questions before you order? Ask a parts specialist.