Cometic PRO2024-NHG Top-End Seal Kit (No Head Gasket) for 2004-06 Subaru Impreza

Vehicle Fitment

• 2004-2006 Subaru Impreza WRX (EJ257 2.5L DOHC Turbo, AWD)
• 2004-2006 Subaru Impreza WRX STI / WRX STI (EJ257 2.5L DOHC Turbo, AWD)

Fitment Notes

• "NHG" = No Head Gasket - this kit **excludes** the cylinder head gasket. Ensure existing head gasket is compatible and in good condition.
• Engine must be EJ257 2.5L DOHC Turbo; non-EJ257, non-turbo Subaru engines are excluded.
• Bore size and head gasket thickness of existing head gasket must be verified to avoid mismatch (compression, sealing, etc.).
• Fitment confirmed through 2006. Models beyond 2006 or modified block/head versions (oversize bore, performance head work) are unconfirmed.

Features

• StreetPro top-end seal kit including seals and gaskets except head gasket: front & rear cam seals, timing cover seal, intake & exhaust gaskets, etc. ([SummitRacing street-pro description])
• High-quality materials: MLS / compatible premium sealing materials where applicable for surviving turbo heat and pressure. ([SummitRacing])
• Designed for turbocharged use in Subaru's EJ257 - meets sealing demands of AWD, boost, heat cycling. ([Throtl listing])
• Budget-friendly option compared to complete gasket kits - avoids redundancy if head gasket already acceptable. ([Throtl, Raptor Racing])
• Includes components needed for top-end rebuild / reseal (excluding head gasket): cam seals, timing cover, etc. ([SummitRacing])
• OEM fitment orientation for seal locations to ensure proper sealing surfaces.
• StreetPro line: good balance of price & durability.
• Includes gasket material types such as AFM, Aramid Fiber, Armor Clad in non-head seal components. ([SummitRacing])

Specifications

• Engine: 2.5 L DOHC Turbo (EJ257), AWD configuration. ([SummitRacing])
• Kit excludes: cylinder head gasket. Includes: camshaft front & rear seals, timing cover seal, intake manifold gasket(s), exhaust crossover / manifold gasket(s), thermostat seal. ([SummitRacing])
• Material: high-quality non-head gasket sealing components (seals, composite/metal gaskets depending on position). ([SummitRacing])
• Fitment years: 2004 through **2006**. **2007+ unconfirmed**. ([SummitRacing])
• Make/Model: Subaru Impreza WRX / WRX STI. All trims using factory EJ257 turbo engine.

Included Components

• 1x Front Camshaft Seal
• 1x Rear Camshaft Seal
• 1x Timing Cover Seal
• 1x Intake Manifold Gasket / Seals
• 1x Exhaust Manifold / Crossover Gasket(s)
• 1x Thermostat or Thermostat Housing Seal
• Various small gaskets/seals (bolts/plugs/seals around head/exhaust/boost passages) except the head gasket itself

Product Description

The Cometic PRO2024-NHG StreetPro Top-End Seal Kit (No Head Gasket) is engineered for Subaru EJ257 2.5 L Turbo engines in 2004-2006 Impreza WRX and WRX STI models. It provides all necessary sealing components for the top end excluding the cylinder head gasket - ideal for applications where the head gasket is still usable or has been replaced separately. It covers camshaft seals (front & rear), timing cover sealing, intake and exhaust manifold gaskets, thermostat or housing seals, and related small seals. Its materials and gasket designs are selected to withstand turbo boost, high temperatures, and the rigors of AWD operation.

Before installing, verify that your existing cylinder head gasket matches the block's bore size and thickness, since mismatch can cause compression losses, leaks, or mechanical interference. Also check that head and block sealing surfaces are flat, clean, and within spec. This kit is confirmed for 2004 through 2006 WRX / STI with EJ257. Use in any model beyond 2006 or modified engine (oversize bore, upgraded heads) is **unconfirmed**. Proper torque sequences, sealing surface prep, and ensuring all seal surfaces are clean and properly mounted are essential to avoid leaks or engine damage.