Heavy Duty Street Sprung Clutch Kit

The ACT SB10-HDSS clutch kit is engineered to provide a significant upgrade for street and light race applications, featuring ACT's most popular Heavy Duty pressure plate and a Performance Street disc. The Heavy Duty pressure plate employs an exclusive diaphragm design that boosts clamp load by 20-50% over stock, reduces deflection, and extends clutch life, with diaphragms treated through a four-stage process for maximum performance. The Performance Street disc utilizes premium organic materials with a high copper content for improved heat transfer and a steel-backed lining for enhanced burst strength and durability. Its reduced marcel ensures faster shift action. Included in this kit is the ACT Monoloc, a single-piece component designed as a direct replacement or upgrade for the traditional two-piece wedge collar and wire ring found in pull-type clutches. The Monoloc's carefully calculated spring tension provides uniform loading on the bearing and pressure plate, ensuring proper alignment irrespective of vehicle modifications or driver input. Constructed from hardened chrome-moly steel, the Monoloc offers long-term service life. This clutch kit is computer spin balanced to within .25 oz-in for smooth, high-RPM reliability, exceeding the balancing of typical production clutches. Expect a pedal effort increase of 15-40% for the Heavy Duty pressure plate. The organic street discs recommend a break-in period of 300-500 miles with mild engagement to ensure optimal performance and longevity. The SB10-HDSS is designed for use in various Subaru models, including the WRX STI (2004-2021), Legacy GT spec.B (2007-2009), and Impreza WRX STI [JDM] (2002-2005), among others with compatible 2.5L H4 engines.