IAG Fire-Lock 2.5L Subaru Head Gaskets (1 Pair w/ Fire-Lock Rings) for EJ25 / EJ257, 100mm, .051", for 14mm Head Studs

Product Fitment:

2004-2013 Subaru Forester XT

2006-2014 Subaru WRX

2004-2021 Subaru STI

2005-2009 Subaru Legacy GT

Proven in IAG's record-setting race builds, the Fire-Lock™ Head Gasket System is the strongest Subaru EJ head gasket solution ever produced. Designed to withstand the extreme demands of high-boost, high-horsepower engines, this system separates combustion sealing from coolant and oil sealing using a dual-component approach based on diesel engine technology.

Developed specifically for IAG’s 950 and 1150 closed deck EJ cases, this system uses precision-machined counterbores to seat custom alloy fire rings above the deck surface, creating a superior combustion seal when torqued with 14mm head studs.

Features:

• Power Rating: Tested and proven beyond 1000 horsepower

• Advanced Design:

  • Fire ring sealing for combustion chambers

  • Composite gasket with silicone beading for fluid sealing

• Inspired by Diesel Technology: Counterbore machined around each bore accepts precision-fit fire rings

• Superior Combustion Seal: Fire rings protrude above the deck surface to seal tightly under head torque

• Precision Materials:

  • Gasket Material: Asbestos-free composite with silicone-based beading

  • Ring Material: Heat-treated proprietary IAG alloy

Specifications:

• Gasket Thickness: 0.051"

• Bore Size: 100mm

• Head Stud Size: 14mm (IAG Studs Required)

• Ring Material: Proprietary IAG-Spec Alloy

• Gasket Material: Composite with silicone sealing bead

Includes:

• (2) IAG Fire-Lock™ Composite Head Gaskets

• (4) IAG Fire-Lock™ Alloy Fire Rings

Note:

• Requires machining to cylinder heads and use of IAG 14mm head studs

• Compatible with IAG 950 and 1150 closed deck EJ25 engine blocks only