DISCLAIMER: This is a made to order item. The lead time for this product is 8-10 weeks.

Flatout GR50-PRO Stage Rally Suspension for 2015–2021 Subaru STI

Take your 2015–2021 Subaru STI to the highest level of stage rally performance with the Flatout GR50-PRO Suspension System — our most advanced, competition-grade rally suspension engineered specifically for serious motorsport.

Built to withstand the extreme demands of rally competition, the GR50-PRO features massive 50 mm pistons housed inside 62 mm shock bodies, delivering exceptional damping control, increased oil capacity, and superior durability in the most punishing rally conditions.

With 3-way adjustable damping, drivers can independently tune high-speed compression, low-speed compression, and rebound, allowing precise suspension setup for gravel, snow, or tarmac rally stages.

Each GR50-PRO kit is hand-assembled, dyno-tested, and fully rebuildable, ensuring consistent race-level performance season after season. Every component — from the CNC-machined high-flow piston to the stainless-steel shim stack and electro-plated nickel cartridges — is designed for maximum performance and reliability under extreme motorsport conditions.

Suspension Travel

• Front Travel: 6.5 inches

• Rear Travel: 6 inches

Key Features

• Designed for Stage Rally Competition → Built for professional and grassroots rally teams.

• 2 Front Assemblies with External Reservoirs → Increased oil capacity and improved heat management.

• 2 Rear Assemblies with External Reservoirs → Consistent damping performance under heavy rally loads.

• 50 mm Pistons / 62 mm Shock Bodies → Massive construction for strength and durability.

• 3-Way Damping Adjustment → Independent control of:

  • High-Speed Compression

  • Low-Speed Compression

  • Rebound

• Radial Bearing Front Assembly → Smoother steering movement and improved articulation.

• Eibach 70 mm Metric Springs → 225 lb/in Front / 225 lb/in Rear for balanced rally performance.

• Secondary Helper Springs → Improved traction and ride balance over rough terrain.

• Electro-Plated Nickel Cartridges → Superior corrosion resistance in harsh rally environments.

• Rebuildable Inverted Shocks → Motorsport-grade seals designed for extreme durability.

• CNC-Machined High-Flow Aluminum Pistons → Precision damping and consistent performance.

• Stainless-Steel Shim Stack → Reliable valving under intense load conditions.

• Medium-Weight Synthetic Shock Oil → Stable damping across varying temperatures.

• Spherical Bearing Upper Mounts (Standard) → Increased articulation and durability.

• Brake and Sensor Line Brackets → Clean and secure line routing.

• Individual Components Available → Simplifies rebuilds, servicing, and tuning.

Why Choose the GR50-PRO?

• Built specifically for professional stage rally competition

• Massive 50 mm piston design for extreme durability and damping capacity

• Full 3-way adjustability for precise suspension tuning across different rally surfaces

• External reservoirs for improved cooling and fade resistance

• Fully rebuildable for long-term motorsport reliability

The Flatout GR50-PRO Suspension System transforms the 2015–2021 Subaru STI into a true rally competition machine, delivering the strength, adjustability, and endurance required for serious motorsport.