GSC Conical Valve Spring Kit for Porsche 991/992 Turbo – GSC5094
The GSC5094 Conical Valve Spring Kit is engineered for the Porsche 991 and 992 Turbo 3.8L</strong platform. Designed to handle extreme RPM and boost levels, this kit includes:
- (24) superfinished lightweight conical valve springs
- (24) titanium retainers for reduced valvetrain mass
- (24) chromoly spring seats for durability under high load
Technical Specifications
| Setup | Coil Bind | Install Height | Seat Pressure | Open Pressure @ 11.5mm Lift | Max Valve Lift |
|---|---|---|---|---|---|
| Intake Conical | 20mm / 0.787" | 33mm / 1.3" | 110 lbs | 272 lbs @ 21.49mm / 0.846" | 11.5mm / 0.453" |
| Exhaust Conical | 20mm / 0.787" | 33mm / 1.3" | 142 lbs | 292 lbs @ 21.49mm / 0.846" | 11.5mm / 0.453" |
Max RPM (OEM Profile): 10,500 RPM
Max Boost: 60 psi
Factory Keepers: Compatible
Valvetrain Mass Reduction
- Intake: -19.1g
- Exhaust: -19.0g
Why Choose Conical Springs?
Conical valve springs are a proven solution for managing valvetrain harmonics. Compared to cylindrical or beehive designs, conical springs offer superior damping characteristics thanks to their variable coil diameter and spacing. This design naturally absorbs shock and vibration, reducing wear and extending component life — a critical advantage in engines operating at the edge of mechanical limits.
Each GSC conical spring undergoes a proprietary multi-step heat treatment and surface finishing process, resulting in a high-performance spring that supports elevated RPMs and aggressive camshaft profiles with confidence.
Whether you're building a high-boost street car or prepping a turbocharged track weapon, the GSC5094 kit delivers the strength, stability, and precision needed for elite-level performance.
Fitment:
- 2014 Porsche 991 Turbo
- 2015 Porsche 991 Turbo
- 2016 Porsche 991 Turbo
- 2017 Porsche 991 Turbo
- 2018 Porsche 991 Turbo
- 2019 Porsche 991 Turbo
- 2020 Porsche 991 Turbo
- 2021 Porsche 992 Turbo
- 2022 Porsche 992 Turbo
- 2023 Porsche 992 Turbo
- 2024 Porsche 992 Turbo
* This kit is designed for the 3.8L twin-turbo flat-six engine used in both 991 and 992 Turbo models. Compatible with factory keepers and supports up to 10,500 RPM and 60psi boost.
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