Cometic Gasket C14084-051 Subaru EJ22/EJ25D .051in MLS Head Gasket 100mm Bore

Vehicle Fitment

• 1995-1998 Subaru Impreza (EJ22E, EJ22T, EJ22ET, EJ25D)
• 1998 Subaru Forester (EJ22E, EJ22T, EJ25D)
• 1995-1999 Subaru Legacy (EJ22E, EJ22T, EJ22ET, EJ25D)
• Compatible with any EJ22 or EJ25D engine build using a 100mm bore diameter - including stroker builds, engine swaps, and hybrid EJ22/EJ25 short block combinations

Fitment Notes

• Bore diameter: 100mm (3.937 in.) - confirm your engine's actual bore diameter before ordering; this gasket is not interchangeable with stock-bore EJ22 (96.9mm) or standard EJ25 (99.5mm) applications without boring
• Fits EJ22E (naturally aspirated), EJ22T (turbocharged), EJ22ET (turbocharged), and EJ25D (DOHC Phase I naturally aspirated) engines at 100mm bore
• Compressed thickness: .051 in. (1.30mm) - near-stock thickness, suitable for standard deck height rebuilds and mildly built street engines; thicker variants are available for stroker builds or compression ratio adjustment
• Installs dry - no additional sealants, copper spray, or adhesives required or recommended; additional sealant can impair MLS gasket sealing performance
• No re-torque required after initial head bolt torque sequence
• Cylinder head and block surface finish recommendation: Ra 50 (2 µin.) or better - MLS gaskets require smooth, properly finished mating surfaces for optimal sealing
• Sold individually - one gasket per package; a complete EJ engine requires 2 gaskets (one per cylinder head)
• Made to order - estimated production time 2-3 weeks; plan accordingly for build timelines

Features

• 3-layer MLS (Multi-Layer Steel) construction - two embossed stainless steel outer layers and one uncoated stainless steel center shim layer for a robust, reliable combustion seal
• Outer layers embossed and coated with Viton (FKM) fluoroelastomer rubber - provides positive micro-sealing against coolant and oil passages; heat resistant to 250°C (482°F)
• FKM/Viton outer coating is also resistant to fuels, oils, and coolants under the high-load, high-temperature conditions of boosted and naturally aspirated EJ builds
• PTFE topcoat on outer layers aids resistance to fretting and improves cold sealing performance on initial startup
• Load-controlled embossments distribute clamping force more evenly across the head gasket surface - reduces bore distortion compared to traditional composite gaskets, protecting ring seal and cylinder geometry
• Ideal for aluminum-head-to-aluminum-block configurations (standard for Subaru EJ-series) - withstands thermal cycling and differential expansion without seal degradation
• No sealant required, no re-torque required - simplifies the build process and eliminates the risk of sealant contaminating the cooling system or oil passages
• Suitable for naturally aspirated, turbocharged, and high-performance/race EJ22 and EJ25D builds at 100mm bore

Specifications

• Part Number: C14084-051
• UPC: 191070472474
• Material: MLS (Multi-Layer Steel)
• Number of Layers: 3
• Compressed Thickness: .051 in. (1.30mm)
• Bore Size: 100mm (3.937 in.)
• Bore Shape: Round
• Outer Layer Coating: Viton (FKM) Fluoroelastomer + PTFE Topcoat
• Orientation: None (symmetric)
• Engine Compatibility: Subaru EJ22E / EJ22T / EJ22ET / EJ25D
• Sealant Required: No
• Re-Torque Required: No
• Production: Made to order - 2-3 week lead time
• Quantity: Sold individually (1 gasket per package; 2 required per engine)

Included Components

• 1x Cometic MLS Cylinder Head Gasket (100mm bore, .051 in. compressed thickness)

Product Description

The Cometic C14084-051 is a 3-layer MLS (Multi-Layer Steel) cylinder head gasket designed for Subaru EJ22E, EJ22T, EJ22ET, and EJ25D engines at 100mm bore diameter, with a .051 in. (1.30mm) compressed operating thickness. It fits the 1995-1998 Subaru Impreza, 1998 Subaru Forester, and 1995-1999 Subaru Legacy in factory or modified form, and is widely used in EJ22/EJ25 hybrid builds where the engine has been bored to 100mm to accept EJ25 pistons in an EJ22 block.

Cometic's MLS design uses load-controlled embossments in the stainless steel outer layers to distribute head bolt clamping force evenly across the sealing surface, dramatically reducing bore distortion compared to composite gaskets - a critical advantage in aluminum-to-aluminum EJ builds where maintaining cylinder geometry directly impacts ring seal and longevity. The Viton-coated outer layers provide a positive micro-seal against coolant and oil without the need for any additional sealant, and the PTFE topcoat further resists fretting on initial cold startups. No re-torque is required after initial assembly. Sold individually - two gaskets are required for a complete EJ engine. This part is made to order with an estimated 2-3 week production lead time.