Product Description
BMW Stage 1 Clutch Kit - SPEC SB351
BMW Stage 1 Clutch Kit - SPEC SB351
SPEC SB351 MAXIMUM TQ RATING: 311 ft/lbs
SPEC Clutch Stage 1 Kits Feature an integrally molded carbon kevlar-based, high performance organic lining that offers smooth engagement and excellent life. This lining has an integrally bonded steel backing for strength under high clamp loads and temperatures. The sprung hub (application dependent) version is double sprung with spring cover relieves for flexibility and heat treated components for strength and durability. Best for street and many track/off-road applications. Some applications require a solid hub based on the vehicles flywheel setup.
SPEC Maximum Torque Recommendations (Measured at the Flywheel):
| Stage 1 | Stage 2 | Stage 2+ | Stage 3 | Stage 3+ | Stage 4 | Stage 5 | |
| Kit Part Number: | SB351 | SB352 | SB353H | SB353 | SB353F | SB354 | SB355 |
| Torque Capacity: | 311 | 355 | 400 | 425 | 493 | 425 | 600 |
Stages 1-3+ recommended for street/strip Stages 4-5 Race only.
SPEC Flywheels are CNC manufactured at an unheard-of .001 tolerance, in an industry where the standard is .010. 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. The automotive component most responsible for insuring optimum clutch performance and life is the flywheel. The flywheel's contribution to power transfer is three-fold. Firstly, the flywheel should provide a consistent and friction enhancing surface for the clutch disc. Flywheels also aid in proper inertia, which is determined by the flywheel weight. Inertia controls the ratio of power to acceleration and can make a vehicle faster or slower based on gear ratio, tire type, vehicle weight, power output and even the location in the powerband output is achieved. The weight of a flywheel and amount of inertia it provides can also effect drivability. Lastly, the flywheel must provide a true balance at rpm, which means no dimensional runout that produces engine damaging and power robbing vibrations and allows smooth engine revolutions. To allow for specific inertia needs, SPEC flywheels are made in high carbon billet steel and aircraft quality billet aluminum. The aluminum and most steel SPEC units are rebuildable 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 and steel materials provide a light and medium weight option for all types of racing. SPEC spends a lot of time and effort on research and development of optimum flywheel dimensions and weights for all types of driving and racing and can optimize your MOI (moment of inertia) to maximize your car's output and performance.
