GSC Power Division 3106-8 Stopper Intake Valve Guides for FA20 Subaru BRZ WRX

Vehicle Fitment

• 2013-2021 Subaru BRZ (2.0L FA20D, RWD)
• 2013-2016 Scion FR-S (2.0L FA20D / 4U-GSE, RWD)
• 2017-2021 Toyota 86 (2.0L FA20D / 4U-GSE, RWD)
• 2015-2021 Subaru WRX (2.0L FA20F Turbo, AWD)

Fitment Notes

• Intake position only. For exhaust stopper-style valve guides, see GSC part number 3105-8.
• This is the stopper-style intake guide. For the smooth (non-stopper) style, see GSC part number 3064-8 - same dimensions, different retention design.
• Stopper design sets proper seating depth automatically during installation, eliminating the need for a separate depth gauge on the press.
• Does not fit second-generation Subaru BRZ (2022+) or Toyota GR86 (2022+) equipped with the FA24D engine - those require separate FA24-specific guides.
• Oversized variants (+0.001" and +0.003" OD) are sold individually under separate part numbers and are not included in this set.

Features

• Stopper design locks each guide at the correct installed depth, eliminating depth measurement during pressing.
• Manufactured from true C67410 Manganese Bronze for superior heat dissipation versus OEM cast iron guides.
• CNC-turned on dedicated precision turning centers for industry-leading concentricity and tolerance control.
• True-to-size OD reduces guide boss honing on cylinder heads in good condition.
• Shaped to improve airflow around the guide bore - not a direct OEM copy design.
• Compatible with standard 5.5mm valve stems and all common valve stem seal options.
• Tight through-hole concentricity minimizes honing time during installation.
• Trusted by engine builders for both street and high-output FA20 builds.

Specifications

• Position: Intake
• Material: C67410 Manganese Bronze
• Total Length: 1.654" / 42.01mm
• Outer Diameter: 0.3964" / 10.07mm
• Valve Stem Diameter: 5.5mm
• Style: Stopper-style (depth stopper)
• Application: Subaru FA20D, FA20F DOHC Boxer-4

Included Components

• 8x GSC Manganese Bronze Stopper-Style Intake Valve Guides (standard size)

Product Description

The GSC Power Division 3106-8 is a set of eight stopper-style Manganese Bronze intake valve guides engineered for the Subaru FA20 DOHC boxer-four engine family. This covers the naturally aspirated FA20D in the first-generation BRZ, Scion FR-S, and Toyota 86, as well as the turbocharged FA20F used in the 2015-2021 WRX. The stopper design is the key differentiator from the smooth-style 3064-8 - it automatically sets the correct installed depth during pressing, which saves the installer time and eliminates the need for a separate depth stop or measuring tool during installation.

Made from true C67410 Manganese Bronze, these guides offer better thermal conductivity and natural lubricity compared to OEM cast iron, which is especially beneficial under sustained high-RPM or boosted conditions. GSC machines these to extremely tight tolerances on dedicated CNC turning centers, reducing bench fitting time and minimizing guide boss honing on well-maintained heads. Whether building a naturally aspirated high-revving BRZ or a turbocharged WRX, the 3106-8 is the stopper-style solution for a precise, reliable FA20 head rebuild.