GSC Power Division 3012-8 Manganese Intake Valve Guides Traditional Smooth 4B11T

Vehicle Fitment

• 2008-2015 Mitsubishi Lancer Evolution X (4B11T, AWD)

Fitment Notes

• Traditional smooth-style guide (no stopper) - the stopper-style intake equivalent for the 4B11T is GSC 3014-8.
• Not compatible with 4G63-based Evo I-IX or DSM platforms - the 4B11T uses a smaller 5.5mm valve stem diameter and a different OD (0.4351" / 11.05mm) vs. the 4G63.
• 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 transfer, and long-term wear resistance over OEM cast iron guides.
• CNC-turned on dedicated precision turning centers to maintain the tightest OD-to-ID concentricity tolerances in the segment.
• Traditional smooth profile for direct compatibility with standard 4B11T head configurations without modification.
• True-to-size OD minimizes guide boss honing on heads that don't require bore service, reducing overall installation time.
• Consistent dimensional accuracy ensures uniform valve-to-guide clearances across all eight intake positions.
• Compatible with GSC 4B11T 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: 1.735" / 44.07mm
• Outer Diameter: 0.4351" / 11.05mm
• Valve Stem Diameter: 5.5mm
• Application: Mitsubishi 4B11T (Lancer Evolution X)

Included Components

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

Product Description

The GSC Power Division 3012-8 is a set of eight traditional smooth-style Manganese Bronze intake valve guides engineered for the Mitsubishi 4B11T engine found in the 2008-2015 Lancer Evolution X. The 4B11T uses a 5.5mm valve stem diameter and a smaller guide OD (0.4351" / 11.05mm) than the preceding 4G63, making these guides specific to the Evo X platform and incompatible with any DSM or Evo I-IX application. Manufactured from true C67410 Manganese Bronze, these guides provide significantly better lubricity, heat dissipation, and wear resistance compared to the OEM cast iron replacements.

Notable on the 4B11T platform is that intake and exhaust guides share identical dimensions (1.735" / 44.07mm length, 0.4351" / 11.05mm OD), so the 3012-8 intake guides are dimensionally the same as the 3011-8 exhaust guides - the part numbers differ only by intended port position. Precision CNC-turned to the tightest concentricity tolerances in the aftermarket, these guides require minimal honing on undamaged guide bosses. For heads that have been bored, individually sold +0.001" and +0.003" oversized options are available. Builders preferring a depth-controlled stopper-style guide should reference GSC 3014-8.

The 3012-8 pairs directly with GSC's Evo X intake valves, valve stem seals, and beehive or conical spring kits for a fully matched valvetrain rebuild on the Lancer Evolution X.