OS SuperLock LSD for Subaru GDB(GRB) WRX STi - REAR
OS SuperLock LSD for Subaru GDB(GRB) WRX STi - REARSKU: SB041-HA
The OS Giken Super Lock LSD uses our patented pressure ring design that allows for smooth, progressive locking. This design is a spline-through-side-gear design that allows for fitment of more friction plates (up to 2x as many as competitors versions).
- All components are chemically heat treated for maximum durability
- All components are constructed from a high-grade steel alloy
- Gears are raw-forged for maximum strength
- Clutch disks are precision-machined simultaneously on both sides to extremely tight tolerances resulting in minimal warpage.
- LSD case is machined from a single billet piece to ensure uniformity.
The OS LSD standard spec allows for low preload while still retaining a fully progressive 100% lock capability. Operation is quiet and the progressive locking allows for smooth predictable locking. When replacing an open diff, equipping an
OS LSD will completely improve the driving experience while maintaining everyday drivability.
Subaru WRX STI (GD/GR) - EJ25
- Ramps -25/38
- Lock Timing - 336
- Total Plates - 20
- Preload - 10S
- Refer to OEM Service Manual for install
If your application is making significantly more power, we offer additional tuning services to your new/used LSD in-house. More power typically means more kick to the differential. We have the ability to speed up or slow down differential action to allow the vehicle to achieve maximum traction.
- Initial torque can be adjusted by using thicker / thinner cone springs
- Lock progression timing can be adjusted by using stiffer / weaker pressure ring springs, allowing the progression of full lock to be fine-tuned to the vehicle/driver
- Ramp angles can be customized by swapping the pressure ring and iron cross for even more tuning possibilities
- TCD spec disks can be installed for increased oil cooling and even smoother operation
Our revolutionary pressure ring houses our patented lock timing system, where springs work in opposition of torque being applied to the LSD. This results in a progressive, smooth, and quiet operation of the clutch discs within the differential. Furthermore, by modifying the spring rate, the rate of which the differential reaches full lock can be adjusted to suit particular vehicle settings and racing styles.
Unlike other manufacturers that utilize modular components, we produce our cams and pressure rings as matching sets. Because the faces of the cams are grounded exactly to match the application area of the pressure ring, torque transfer is smooth and consistent throughout the lock range.
The unique “spline-through” side gears allows our LSD to house more clutch discs than other competitors. Also, due to the relatively large size, it provides superior durability and torque transfer.
The discs are precision-machined simultaneously on both sides to extremely tight tolerances to reduce flatness deviations and to eliminate the need to perform the tedious “figure 8” break-in period. By using as much as twice as many clutch discs than competing brands, our differential provides superior torque hold, while also reducing the “clunkiness” of traditional clutch-type LSDs. This also results in enhanced durability and reduced wear as torque hold is spread out over a higher amount of friction surfaces.
The case and all components are constructed from a high-grade steel alloy, and then chemically heat treated for increased durability. The extra rigidity created ensures that the internal components stay within their tight tolerances, allowing the differential to function with watch-like precision.