Xtreme Performance Race Sprung Ceramic Clutch Kit incl. SMF & CSC Socata Tbm 850 The Encyclopedia of Aircraft David C. Eyre. At Xtreme Clutch, we strive to offer a variety of clutch options for each vehicle to ensure a clutch solution is available for every vehicle application. Whether you are modifying a road vehicle or building a race car from scratch, we have the clutch solution for you. Our upgrades are divided into different stages depending on the friction disc material and the number of friction discs. Racing Sprung Ceramic 1R Stage 1R Racing Sprung Ceramic Motorsport upgrades are designed specifically for motorsport applications that require a higher torque capacity than the 1B equivalents. Each Stage 1R kit includes an Extra Heavy Duty pressure plate with even higher clamping force and a sprung ceramic friction disc. Recommended for: Specifically for motorsport applications such as circuit, rally, drifting and drag racing. Notes: This clutch kit includes a Single Mass Flywheel (SMF) and Concentric Slave Cylinder (CSC)