IAG Trojan Subaru EJ25 Closed Deck Short Block
The IAG Trojan Short Block starts with brand new Subaru 2.5L engine case halves.
IAG machines the case halves assembled together in our Haas VF-4SS CNC mill to accept the IAG CLOSED Deck Inserts that transform the block into a solid deck.
The unique inserts feature small passages that allow needed coolant flow to the deck surface. The case halves are CNC machined with O-ring receiver grooves around the bore surface as well as drilled and tapped to accept 1/2" head studs that greatly reduce head gasket failure during high cylinder pressure scenarios.
Next, the short block is Deck Plate bored and honed to 99.75mm in our in-house Sunnen SV-30 the most advanced automotive cylinder hone available.
IAG‘s in-house honing process is able to set custom piston to wall clearances to best fit your needs.
The modified case halves are then assembled using a new 2017+ Subaru 2.5L nitride treated STI crankshaft that is matched to ACL or King race main bearings. IAG-Spec Tuff H-Beam connecting rods and ARP 625+ rod bolts are utilized along with ACL or King race rod bearings.
The case halves are sealed with new OEM main/case bolts and sealant. Finally, IAG-Spec 99.75mm JE FSR 2618 Forged Pistons and electroless nickel plated tops and ring area as well as upgraded .250" / .906" H13 wrist pins are added to finish the Trojan short block.
- Additionally, all IAG-Spec piston skirts utilize the JE Perfect Skirt coating.
IAG Trojan Closed Deck Includes:
Case Halves - Converted to Closed Deck using brand new Subaru OEM case halves, bored and honed to 99.75mm.
O-Ringing - Machine and O-Ring Deck Surface
Head Studs - Machine Case to 1/2" 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 / 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.
Additional Options Available:
Head Studs - IAG 1/2" ARP Head Stud Set - $499.99
Oil Pump - Subaru JDM 12mm High Volume Oil Pump - $219 or 11mm Subaru Oil Pump - $199.95
Head Gaskets - JE Pro Seal .039 inch Head Gaskets (PN# SB1001-039 for D25 & B25 Heads, PN# SB1003-039 for V25, W25 & N25 Heads)
IAG Oil Pickup - Upgraded oil pickup featuring heavy gauge steel tubing, 2 point bracket & mesh filter - $129.99
Hardware / Seal Option - $105.99 (Wrist pin plugs, washers, separator cover, bolts, etc. In case you don’t want to transfer from the original engine).
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 Recommendations:
*IAG Recommends JE Pro Seal .039 inch head gaskets
JE PN# SB1001-039 are for use with S20, B25 & D25 Cylinder Head Castings (04-06 STI, 06-14 WRX, 04-13 FXT, 05-12 LGT, 02-05 WRX)
JE PN# SB1003-039 are for use with V25, W25 & N25 Cylinder Head Casting (2007-19 STI)
The IAG Trojan Short Block has a power output rating of 750BHP.
*All IAG short blocks are balanced and blueprinted.
This block fits the following Subaru's:
Model Year & Fitment
2002 Subaru WRX (Requires Mods)
2003 Subaru WRX (Requires Mods)
2004 Subaru WRX (Requires Mods)
2005 Subaru WRX (Requires Mods)
2006 Subaru WRX
2007 Subaru WRX
2008 Subaru WRX
2009 Subaru WRX
2010 Subaru WRX
2011 Subaru WRX
2012 Subaru WRX
2013 Subaru WRX
2014 Subaru WRX
2004 Subaru STI
2005 Subaru STI
2006 Subaru STI
2007 Subaru STI
2008 Subaru STI
2009 Subaru STI
2010 Subaru STI
2011 Subaru STI
2012 Subaru STI
2013 Subaru STI
2014 Subaru STI
2015 Subaru STI
2016 Subaru STI
2017 Subaru STI
2018 Subaru STI
2005 Subaru Legacy GT
2006 Subaru Legacy GT
2007 Subaru Legacy GT
2008 Subaru Legacy GT
2009 Subaru Legacy GT
2004 Subaru Forester XT
2005 Subaru Forester XT
2006 Subaru Forester XT
2007 Subaru Forester XT
2008 Subaru Forester XT
2009 Subaru Forester XT
2010 Subaru Forester XT
2011 Subaru Forester XT
2012 Subaru Forester XT
2013 Subaru Forester XT
Are you ready to choose which one you want?
Click on which one you are interested in and this will take you to your email editor to send us an email to set up a time and get started.
All requests / orders must be put in play by setting up a time to come to the shop to go over all details, cover all aspects of the build and put down a deposit. Details matter.
IAG Magnum Subaru EJ25 Closed Deck Short Block