GSC Power Division 3028-8 Manganese Bronze Intake Valve Guide Traditional Subaru

Vehicle Fitment

• 2002-2014 Subaru Impreza WRX (EJ205, AWD)
• 2004-2021 Subaru Impreza WRX STI (EJ257 / EJ257B, AWD)
• 2005-2012 Subaru Legacy GT / Outback XT (EJ255, AWD)
• 2004-2013 Subaru Forester XT (EJ255, AWD)
• JDM 1999-2007 Subaru Impreza WRX STI (EJ207, AWD)

Fitment Notes

• Traditional smooth-style guide (no stopper) - seating depth must be measured and verified during installation; the stopper-style intake equivalent for this engine family is GSC 3026-8.
• Traditional smooth-style exhaust equivalent is GSC 3027-8.
• Fits EJ205, EJ207, EJ255, EJ257, and EJ257B engines - does not fit EJ20 SOHC or non-turbocharged EJ25 variants with different valve stem or guide boss specifications.
• Standard OD sizing; light honing of the guide boss may be required depending on head condition and target clearance specification.
• Oversized OD options (+0.001" and +0.003") are available individually for heads requiring bore service.

Features

• Manufactured from true C67410 Manganese Bronze for superior lubricity, heat conductivity, and long-term wear resistance over OEM cast iron guides.
• Traditional smooth profile for direct compatibility with standard EJ-series head configurations without modification.
• CNC-turned on dedicated precision turning centers to maintain the tightest OD-to-ID concentricity tolerances in the aftermarket.
• True-to-size OD minimizes guide boss honing on heads that don't require bore service, reducing overall installation time.
• Intake-specific length (1.560" / 39.62mm) correctly sized for EJ-series intake port geometry - significantly shorter than the exhaust guide (1.873").
• Compatible with GSC EJ-series intake valves, valve stem seals, and spring kits for a complete matched valvetrain rebuild.

Specifications

• Position: Intake
• Style: Traditional Smooth (no stopper)
• Material: Manganese Bronze (proprietary C67410 blend)
• Total Length: 1.560" / 39.62mm
• Outer Diameter: 0.4357" / 11.07mm
• Valve Stem Diameter: 6mm
• Application: Subaru EJ205, EJ207, EJ255, EJ257, EJ257B

Included Components

• 8x GSC Power Division Manganese Bronze Traditional Intake Valve Guides (Standard OD)

Product Description

The GSC Power Division 3028-8 is a set of eight traditional smooth-style Manganese Bronze intake valve guides for Subaru's turbocharged EJ20 and EJ25 engine family, covering the EJ205, EJ207, EJ255, EJ257, and EJ257B across the WRX, WRX STI, Legacy GT, Outback XT, and Forester XT. The 3028-8 is the smooth counterpart to the stopper-style 3026-8 - sharing the same dimensions (1.560" / 39.62mm length, 0.4357" / 11.07mm OD, 6mm stem) but without the integrated depth collar. This makes it the preferred choice for builders and machine shops that are already set up to verify guide protrusion depth manually and prefer to work with a smooth profile.

Made from true C67410 Manganese Bronze and CNC-turned to the tightest OD-to-ID concentricity tolerances available in the aftermarket, the 3028-8 provides improved lubricity against the valve stem, better thermal conductivity, and significantly longer wear life compared to OEM cast iron intake guides - all important factors when running aggressive cam profiles or high-boost builds. Minimal honing is required on undamaged guide bosses, and individually sold +0.001" and +0.003" oversized options are available for heads requiring bore service. Builders who prefer stopper-style installation should reference GSC 3026-8.

A straightforward component for any EJ-platform head rebuild, the 3028-8 pairs directly with GSC's EJ-series intake valves, Viton valve stem seals, and beehive or conical spring kits for a fully matched valvetrain on any WRX, STI, Legacy GT, Outback XT, or Forester XT.