IAG Performance ARP 14mm Head Stud Set – Subaru Models (inc. 2002+ WRX / STI)

IAG Performance ARP 14mm Head Stud Set — 2002+ WRX / STI

ARP 14mm Head Studs for High-Performance EJ and FA20 Builds
The IAG Performance ARP 14mm Head Stud Set provides the clamping force required to prevent cylinder head lifting in high-performance Subaru applications. Manufactured by ARP, these 14mm studs are the standard head stud upgrade for IAG short block builds at the 950 and 1150 power tiers. The engine case must be drilled, tapped, and machined to accept 14mm studs — a procedure included in all IAG 950 and higher short blocks.

DETAILS

• Manufacturer: ARP (American Racing Products)
• 14mm diameter for increased clamping force over OEM
• Prevents cylinder head lifting under high boost
• Required for IAG Fire-Lock head gasket system
• Requires case machining for 14mm fitment (standard on IAG 950+ short blocks)
• Included in IAG Long Block packages as standard
• Fits: 2002+ WRX / STI (with machined case)

ARP 14mm Studs and the Fire-Lock System
IAG’s Fire-Lock head gasket system is designed to work in conjunction with 14mm head studs. The Fire-Lock rings create a superior combustion seal, and the 14mm ARP studs provide the clamping force to hold that seal at the cylinder pressures generated by high-boost applications. The two components are designed as a system — using them together provides the maximum head sealing integrity available for the EJ platform.

Case Machining
The engine case must be drilled, tapped, and bored for 14mm stud fitment before installation. This machining is a standard step in the preparation of all IAG 950 and 1150 short blocks. If you are upgrading an existing engine without a new IAG short block, the case machining must be performed by a qualified engine builder.

Included in Long Block Packages
IAG’s 950 and 1150 Long Block engine packages include the 14mm ARP head stud set as standard. If you are purchasing a complete IAG long block, you do not need to purchase this stud set separately.

Why Choose IAG Performance

IAG Performance has been building Subaru-specific engine and drivetrain components since 2001, and in that time they have become the standard by which serious Subaru builds are measured. Based in Westminster, Maryland, IAG designs, machines, and assembles their products in-house using Haas CNC equipment and their own engineering team. Their catalog spans everything from short blocks and long blocks rated to 1150 BHP all the way down to the fuel system, oiling, and drivetrain hardware that keeps modified Subarus running reliably for years. Every IAG product exists because a problem needed a better solution than what was available — and the engineering shows.

The RallySport Take

The IAG ARP 14mm head stud set is the standard sealing hardware for IAG 950 and 1150 tier builds. If you are building with IAG’s Fire-Lock head gasket system, these studs are the required hardware. ARP quality, correct diameter, designed to work with the IAG sealing system.

Fitment