Spec Clutch SM88A Aluminum Flywheel SFI-Certified Billet Performance

The SPEC SM88A is a precision-machined, aircraft-quality billet aluminum flywheel engineered for high-performance street and racing applications. Manufactured to an industry-leading .001-inch CNC tolerance — ten times tighter than the industry-standard .010 — this flywheel delivers perfect rotational balance and a consistently flat clutch disc bedding surface, both critical factors for reliability and safety in competitive driving environments. All SPEC aluminum flywheels carry SFI certification.

The flywheel is the drivetrain component most responsible for optimum clutch performance and longevity, and it serves three essential functions:

• Friction Surface: Provides a consistent, friction-enhancing contact surface for the clutch disc to ensure maximum grip and holding power
• Inertia Management: Controls the ratio of power to acceleration — flywheel weight directly affects drivability, throttle response, and performance based on gear ratio, vehicle weight, and power output
• Precision Balance: Maintains true rotational balance at high RPM, eliminating dimensional runout that causes power-robbing vibrations and engine wear

The SM88A flywheel body is constructed from tempered aircraft-quality billet aluminum (6061-T6 or 2024-T3) for maximum strength at the lightest possible weight. A replaceable 1/4-inch thick 1050 high-carbon alloy steel friction plate is included, specially formulated for optimum clutch bedding and holding power and compatible with all friction disc materials. The friction plate is secured with aerospace-grade fasteners for exceptional strength and corrosion resistance. The ring gear is pressed on, heat-treated for longevity, and secured with grade-10 fasteners.

Compared to a stock steel flywheel, this aluminum unit is approximately half the weight, enabling faster engine revving, reduced drivetrain drag, and quicker throttle response. The SM88A is fully rebuildable, with the friction plate replaceable to restore the flywheel to like-new condition. Designed, hand-built, and tested in the USA.

Key Features:

• Aircraft-quality billet aluminum construction (6061-T6 or 2024-T3)
• CNC machined to .001-inch tolerance for perfect balance and flat seating surface
• Replaceable 1050 high-carbon alloy steel friction plate (1/4-inch thick)
• Secured with aerospace-grade fasteners and stainless steel rivets
• Heat-treated ring gear with grade-10 fasteners
• SFI certified for competitive and racing environments
• Approximately 50% lighter than OEM steel flywheels
• Rebuildable design for long-term serviceability
• Suitable for street, drag, autocross, road race, and pulling applications
• Designed, hand-built, and tested in the USA