ACT Mod-Twin 225 Extreme Rigid Race Twin Disk Clutch Kit 2004-2021 STI

The Mod-Twin 225 XT Rigid Race Kit is designed for high-powered AWD racing vehicles, providing extreme torque capacity and ultra-fast shifts. It combines twice the ceramic friction surfaces with a solid Mono-Drive hub in a fully modular design. Each diaphragm spring undergoes a four-stage heat treatment for consistent light pedal feel. Puck-style ceramic friction plates deliver high friction coefficient, superior heat capacity, and long-lasting durability. Torque is uniformly transferred through a Mono-Drive chrome-moly hub, extending input shaft life with a single continuous spline. The lightweight, rigid design allows rapid shifting and trouble-free service. The kit includes a CNC-machined, dynamically balanced flywheel, pressure plate cover, diaphragm spring, puck-style ceramic friction plates, rigid Mono-Drive hub, floater, patented Monoloc collar, release bearing, alignment tool, and pilot bearing (if needed). Mod-Twin clutches are fully rebuildable, with most components available separately.

Specs

• Torque Capacity: 1120 ft/lbs (214% over OE)
• Disc Material: Ceramic
• Disc Diameter: 8.8 in / 225 mm
• Input Shaft Diameter: 1 in
• Pressure Plate Type: Xtreme
• Product Weight: 28.1 lbs
• SFI: 1.2

Performance Characteristics

• Feel: Predictable aggressive engagement, light pedal effort, quick shifting, possible start-off judder with mild to moderate transmission gear noise
• Life: Forged aluminum cover, Mono-drive hub, exclusive diaphragm, premium friction materials, and hardened wear points provide long-lasting performance under the most demanding conditions
• Quality: Combines robust design, strategic features, choice materials, and close tolerances for maximum performance and high heat tolerance
• Recommended Use: Drag, Road, or Rally Racing
• ACT Difference: Ultra-durable, customer-serviceable twin disc clutch, 100% clamp load tested, dynamically balanced, and SFI certified