Spec Clutch SF15A Billet Aluminum Flywheel SFI Certified

The Spec Clutch SF15A is a billet aluminum flywheel CNC machined to an industry-leading .001-inch tolerance — ten times more precise than the industry-standard .010 tolerance. This exceptional precision ensures perfect rotational balance and a flawlessly flat clutch disc bedding surface, delivering maximum reliability and safety in high-stress performance and racing environments. The SF15A carries full SFI certification, making it compliant with sanctioned motorsport requirements.

Key Features:

• CNC machined from aircraft-quality billet aluminum for a lightweight, high-revving advantage
• Precision ground to a .001-inch machine tolerance — 10x tighter than industry standard
• Replaceable steel friction plate specially formulated for optimum clutch bedding and holding power
• Rebuildable construction — replacement friction plates are available separately
• SFI certified for use in sanctioned drag, road race, drift, autocross, and rally applications
• Minimized dimensional runout eliminates engine-damaging vibrations and power-robbing imbalance
• Optimized Moment of Inertia (MOI) for faster revs, reduced rotating mass, and quicker throttle response compared to OEM cast steel flywheels

Flywheel weight plays a critical role in overall drivetrain performance. A lighter aluminum flywheel reduces rotational inertia, enabling faster engine acceleration and sharper throttle response — ideal for track, drag, and high-performance street applications. The SF15A's replaceable friction plate is engineered from a friction-enhancing steel alloy designed to maximize clutch engagement consistency and longevity. Spec engineers invest heavily in research and development to optimize flywheel dimensions and MOI across a wide range of applications, ensuring this flywheel complements your engine output, gear ratios, and driving environment.