SKU: B1023
GSC P-D Subaru FA20 Viton 5.5mm Valve Stem Seal - Set of 500 for 2015-2021 WRX STI
GSC Power-Division Viton valve stem seals fit Subaru FA20F engines in 2015-2021 WRX STI models. These seals meter oil precisely to intake and exhaust valves reducing consumption and maintaining valvetrain lubrication during high-rpm operation. The bulk set of 500 supports race teams shops and builders tackling multiple FA20 engine refreshes.
Key Features
- Viton Construction: Resists temperatures up to 400°F prevents hardening and cracking for long-term sealing in boosted FA20 applications
- 5.5mm Low Stem Design: Matches OEM Subaru FA20 valve stems for drop-in fit without guide wear or oil bypass issues
- Bulk Set of 500: Provides enough seals for 31 complete FA20 engines ideal for professional rebuilds and high-volume service
- Precision Molded Seals: Ensures uniform tension and zero leaks supporting consistent power delivery in track and street use
- High-Durability Material: Outperforms stock rubber seals in oil resistance and heat cycling for sustained valvetrain performance
Product Notes
- Inspect valve guides for wear before installation to achieve full sealing performance
- Store seals in original packaging away from contaminants and direct sunlight
- Packaged in protective bulk container to prevent damage during transit
Installation Notes
- Professional installation recommended.
- Use a valve seal driver tool sized for 5.5mm stems to seat seals evenly without distortion
- Compatible with stock or aftermarket valve guides clean thoroughly with solvent prior to assembly
This Part Fits
| Year | Make | Model | Submodel |
|---|---|---|---|
| 2015-2021 | Subaru | Impreza | WRX STI |
| 2015-2021 | Subaru | WRX | STI |
Why Choose GSC Power-Division?
- Proven in professional motorsports with championship-winning Subaru teams
- Manufactured in USA with rigorous quality controls for consistent results
- Engineered specifically for high-boost FA applications like the STI FA20F
Frequently Asked Questions
-
Q: Will these seals fit 2015-2021 Subaru WRX STI FA20 engines?
A: Yes designed exclusively for FA20F engines in all 2015-2021 STI models including USDM JDM and Euro variants with 5.5mm valve stems -
Q: What makes Viton better than stock seals?
A: Viton handles extreme heat oil additives and boost pressure far longer than OEM rubber reducing smoke and oil burn over thousands of miles -
Q: What is the warranty on these seals?
A: GSC offers a limited lifetime warranty against manufacturing defects when installed by certified technicians
Shipping & Handling
- Method: UPS Ground or USPS Priority
- Availability: In stock - ships same or next business day
- Packaging: Secure bulk box 6 x 4 x 4 inches
- Weight: 0.7 lbs
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