Spec Clutch SB663F Stage 3 Plus Performance Clutch Kit

The Spec Clutch SB663F Stage 3 Plus is the flagship performance clutch kit designed for heavily modified street and race engines that demand more torque capacity than the standard Stage 3 can provide. Built for drivers who need serious power handling without sacrificing daily drivability, the Stage 3 Plus delivers a manageable, friendly engagement even under high-performance conditions.

At the heart of this kit is a carbon semi-metallic full-face friction disc, engineered to deliver outstanding service life, a superior friction coefficient, and excellent drivability in a single package. The disc hub is double-sprung with spring cover reliefs for added flexibility, while heat-treated internal components ensure long-term strength and durability under repeated high-load use.

Kit Includes:

• High-clamp performance pressure plate
• Full-face carbon semi-metallic friction disc
• High-torque sprung hub and disc assembly
• Release bearing
• Installation tool kit

Intended Use:

• Street / Daily Driving
• Drag Racing
• Drifting
• Road Racing
• Autocross
• Pulling
• Rally

The Spec SB663F Stage 3 Plus is proudly manufactured in the U.S.A. and represents a significant step up in torque capacity and wear characteristics compared to the Stage 3, while still maintaining the street manners needed for everyday use.