ACT Mod-Twin HD Street Clutch Kit – 2004-2020 Subaru WRX STI (Sprung Mono-Drive Hub)

Designed for high-powered AWD street machines, the ACT Mod-Twin 225 Heavy Duty Sprung Street Clutch Kit (T1S-S05) delivers massive torque capacity without sacrificing drivability. With its modular twin-disc design and advanced Mono-Drive sprung hub, this clutch provides smooth engagement, a light pedal feel, and the durability needed to handle serious power on the street or strip.

Key Features & Benefits

• Massive Torque Holding: Rated up to 700 ft-lbs of torque—an impressive 97% increase over stock capacity.
• Sprung Mono-Drive Hub Design: Minimizes driveline shock and torsional vibration while extending input shaft life.
• Dual Organic Friction Discs: Premium, high-copper organic material ensures stable friction, excellent heat tolerance, and long-lasting performance.
• Consistent Pedal Feel: Diaphragm springs undergo a 4-stage heat treatment process for reliable, light pedal effort under extreme conditions.
• Fully Modular & Rebuildable: Components can be replaced individually, offering long-term value and easy serviceability.

Technical Specifications

What to Expect

• Feel: Light pedal effort with soft, progressive engagement and smooth shifting. Expect OE to mild gear noise under load.
• Longevity: Built for long-term durability with forged aluminum components, hardened wear points, and premium materials throughout.
• Build Quality: Each kit is precision-engineered, computer-balanced, and built to withstand high heat and demanding use.

The ACT Difference

The ACT Mod-Twin goes beyond conventional twin-disc designs. By strategically engineering around common compromises, ACT delivers a high-performance clutch that's not only incredibly strong but also streetable and serviceable. Every unit is 100% clamp load tested, dynamically balanced, and SFI certified for trusted performance.