Spec Clutch SZ455 Stage 5 Full-Metallic Clutch Kit

The SPEC SZ455 Stage 5 Clutch Kit is SPEC's highest-performance single-disc clutch solution, purpose-built for drag racing, pulling competitions, and other high-demand motorsport applications. Featuring a full-metallic rigid iron disc with the maximum possible friction coefficient, this kit delivers instant, aggressive clutch engagement for drivers who need uncompromising power transfer at the limit.

The Stage 5 is best suited for seriously modified race engines and applications that require a slipper clutch or progressive torque-induced engagement. This is a race-only clutch — while technically street-drivable, the harsh engagement characteristics make it unsuitable for daily driving or casual street use.

Key Features:

• Full-metallic rigid iron disc assembly with maximum friction coefficient
• High clamp pressure plate (adjustability available on select applications)
• Solid 12-rivet hub, heat-treated for strength and long-term durability
• Rated up to 450–510 ft-lbs torque capacity
• Includes bearing and tool kit (select applications)
• SFI approved clutch kit and flywheel
• Optional billet aluminum pressure plate and billet flywheel friction plate kit available

Intended Use: Drag racing, pulling

Installation Note: If not using a new SPEC flywheel, the existing flywheel must be resurfaced prior to installation to ensure proper friction surface integrity. A minimum 500-mile break-in period is required before full-throttle engagement or power shifting.