Spec Clutch ST804 Stage 4 Performance Clutch Kit

The Spec Clutch ST804 Stage 4 Clutch Kit is a race-grade clutch system engineered for heavily modified engines where maximum torque capacity, instantaneous engagement, and reduced rotating mass are the priority. As a solid-hub evolution of the Stage 3, this kit is purpose-built for competitive motorsport applications and is not intended for street use due to its aggressive, unforgiving engagement characteristics.

Key Features:

• Solid 8-Rivet Hub: Features a rigid, solid 8-rivet hub construction — a significant step up from the sprung hub found in Stage 3 kits — delivering direct, zero-slip power transfer
• Heat-Treated Assembly: The entire hub and carrier assembly is heat treated for enhanced strength and long-term durability under extreme racing loads
• High-Clamp Pressure Plate: Upgraded high-clamp pressure plate delivers increased clamping force to handle elevated torque output from modified engines
• Carbon Semi-Metallic Friction Disc: Available in 3, 4, or 6-puck configurations — choose 3-puck for the lightest possible rotating mass, 6-puck for comparatively smoother engagement, or 4-puck as a balanced compromise between the two
• Complete Kit: Includes the pressure plate, friction disc, release bearing, and tool kit for a straightforward installation
• SFI Approved: Every Spec Clutch kit and flywheel carries SFI approval for sanctioned racing applications

Intended Driving Environments: Drag Racing, Drift, Road Racing, Rallye, Pulling, Circle Track

Installation Note: Unless installing alongside a new Spec flywheel, the existing flywheel must be resurfaced prior to installation to ensure proper friction surface integrity.