SPEC flywheels are CNC manufactured at an unheard-of .001 tolerance. This precision manufacturing process ensures perfect balance and a perfectly flat bedding surface for the clutch disc, both of which also contribute to the ultimate in safety for competitive environments. All SPEC flywheels carry SFI certification. Provides a consistent and friction enhancing surface for the clutch disc. Also aids in proper inertia, which is determined by the flywheel weight.
To allow for specific inertia needs, SPEC flywheels are made in aircraft quality billet aluminum. The aluminum SPEC units are able to be rebuilt and feature a replaceable steel friction plate that is made from a friction- enhancing steel metal specially formulated for optimum clutch bedding and holding power. The aluminum materials provide a light weight option for all types of racing.
Tech Tip: If you have a 1965-1966 Mustang with an original 160 tooth flexplate/flywheel the 157 tooth can be used as a replacement as long as you have a 10.5 in bolt circle and are using the "small" bellhousing. The small bellhousing is typically aluminum, the larger 164 tooth is typically cast iron. The 164 tooth flexplate/flywheel can NOT be used as replacement for the 160.