Spec Clutch SB23S Steel Flywheel SFI-Certified CNC Billet

The SPEC SB23S Steel Flywheel is a high-performance, SFI-certified flywheel precision CNC machined to an industry-leading .001" tolerance — ten times tighter than the industry-standard .010". This exceptional precision ensures perfect rotational balance and a perfectly flat clutch disc bedding surface, delivering maximum safety and reliability in both street performance and competitive racing environments.

Key Features:

• SFI Certified — meets strict safety standards for competitive motorsport use
• CNC machined to .001" tolerance — 10x tighter than industry standard for superior balance and surface flatness
• High carbon billet steel construction — provides medium-weight inertia characteristics ideal for a wide range of racing and performance applications
• Replaceable steel friction plate — made from friction-enhancing steel specially formulated for optimum clutch bedding and holding power
• Rebuildable design — extends service life and reduces long-term ownership costs
• Zero dimensional runout — eliminates engine-damaging vibrations and power-robbing harmonics for smooth, consistent engine revolutions
• Optimized MOI (Moment of Inertia) — engineered dimensions and weight deliver the ideal balance of acceleration response and drivability

The flywheel is the single most important component for optimizing clutch performance and longevity. It serves three critical functions: providing a consistent, friction-enhancing surface for the clutch disc; contributing the correct inertia based on its weight to manage the ratio of power to acceleration; and maintaining true rotational balance at all RPM levels. SPEC engineers invest heavily in R&D to optimize flywheel dimensions and weights across all performance and racing applications, ensuring your vehicle's moment of inertia is dialed in for maximum output.