Spec Clutch SF503F-9 Stage 3 Plus Performance Clutch Kit

The SPEC SF503F-9 Stage 3+ Clutch Kit is the flagship performance stage designed for high-powered street or race applications that demand strong holding capacity without sacrificing daily drivability. Built around a carbon semi-metallic full-faced friction disc, this clutch kit delivers an exceptional balance of torque capacity, longevity, and pedal feel that puck-style race clutches simply cannot match.

At the heart of the Stage 3+ is a high-clamp pressure plate paired with a full-face disc rated to handle up to 875 ft-lbs of torque at the flywheel. The full-face design eliminates the harsh on/off engagement associated with race-only clutches, making it equally at home on the street or the strip. The disc measures 11" in diameter with a 23-tooth, 1" spline hub using a 6-spring assembly for smooth power transfer.

The hub features a double-sprung design with spring cover reliefs for added flexibility and reduced drivetrain shock. All internal hub components are heat-treated for enhanced strength and long-term durability under repeated high-load use. The 9-bolt pressure plate cover pattern is compatible with a wide range of performance flywheels.

Key Features:

• Carbon semi-metallic full-faced friction material for superior grip and long service life
• High-clamp pressure plate for maximum clamping force
• 875 ft-lb torque capacity at the flywheel
• High-torque sprung hub and disc assembly — 11" x 23T x 1", 6-spring design
• Double-sprung hub with spring cover reliefs for flexibility
• Heat-treated components for strength and durability
• 9-bolt pressure plate cover pattern
• Includes bearing and installation tool kit

Intended Use:

• Street performance
• Drag racing
• Autocross
• Road racing
• Rally
• Drifting
• Pulling

The SPEC Stage 3+ bridges the gap between an aggressive race clutch and a streetable daily driver, making it the ideal upgrade for forced-induction or high-output builds that see both track and street duty.