NISMO GT L.S.D.

The GT L.S.D. Series is a limited slip differential tested in actual battle in the Japan GT series. It was used in the 2002 season by the GT500 XANAVI NISMO GT-R and the GT300 Daishin Advan Silvia, and currently is preferred by user in production car-basis motorsports such as D1 Grand Prix, tuning car racing and Super Taikyu. Street use, circuit attack and drifting,

Nismo is now offering 3 types of L.S.D.
GT L.S.D. Basic
GT L.S.D. Pro
GT L.S.D. Pro TT - Model

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GT L.S.D. Basic (1.5 way & 2.0 way)
(Fixed initial torque internal pressure basic model)

20 LARGE DIAMETER PLATES
The plates which are the slipping faces of the L.S.D. have been increased in diameter by 55% over existing models; by increasing the number of plates to 20 the changeover from slip to lock has become dramatically smoother. The load on each sliding face has been decreased compared to previous models, while durability has been increased by 30%.

SECURING THE MOST SUITABLE PLATE TOOTH AREA
The plates have 16 outside teeth which pick up the power input from the engine. Receiving the input from the road surface are eight interior teeth, while the combination of case and side gear, which catch and hold the plate gears, have been set with greater precision, creating a large-diameter-plate L.S.D. that completely controls slip judder. Because of this, stable, smooth, effective power and increased durability are provided.

USE OF HIGH QUALITY PLATES
NISMO-exclusive special heat treatment to the surfaces of the plates ensures that there is no catching during slippage, providing a smooth, linear effect. Because of this special heat treatment, the plates work in harmony during the initial break-in period, controlling plate scorching and loss of initial torque.

HIGH LEVEL OF CONTROL
The GT L.S.D. is not simply an L.S.D. that provides more effective strength. It also reduces drive loss from occurring when attacking in circuit racing, and provides the solid traction need for improved cornering speed. These characteristics also provide improved angle control in drifting.

GT L.S.D. Cam Angles
GT L.S.D. (Driving/coasting)
Type - 1.5 way - 55°/1°
Type - 2 way - 55°/45°



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GT L.S.D. Pro (1.5 way & 2.0 way)

VARIABLE INITIAL TORQUE INTERNAL PRESSURE FUNCTION (6.5-8.5-14.0kgf *1)
*1 The design standard values for initial torque outputs are 6.5-8.5-14.0kgf. After break-in (plates are working together) these figures will stabilize at LOW: 5.0 to 5.5; MIDDLE: 7.0 to 7.5; HIGH: 12.5 to 13.0kgf. Product ships at the MIDDLE setting.

The GT L.S.D. Pro allows for the setting of three initial torque values (LOW/MIDDLE/HIGH: 6.5-8.5-14.0kgf) without the disassembly of the L.S.D. itself. This allows for easy change of initial torque in response to changing driving style, tires, suspension, tuning or running conditions. And as initial torque decreases as parts age, changing the initial torque-LOW two times, MIDDLE once-overhaul costs can be saved. GT L.S.D. Pro is the ideal solution for those who are spending too much time working on their L.S.D. In all other ways, the specifications are the same as for the standard GT L.S.D..

Recommended Initial Torque
Circuit: LOW
Street: LOW
Drifting: Middle

GT L.S.D. Pro Cam Angles
GT L.S.D. Pro(Driving/coasting)
Type - 1.5 way - 55°/1°
Tye - 2 way - 55°/45°

STRUCTURE OF VARIABLE INITIAL TORQUE FUNCTION
The plate spring within the pinion mate shaft (3 in the photo) and the plate which is pressed by the plate spring (2 in the photo) function as a set. Three different grooves of varying depth are cut into the plate (2); the initial torque setting is changed by depressing the spring and moving the plate to the groove corresponding to the desired initial torque.

The plate (no. 2 in the photo) is pressed (right side of illustration) by the cap (no. 1 in the photo) and reset.



TO CHANGE INITIAL TORQUE
Car is raised on a jack; with the right side flange removed, a single wrench is all that is needed to change initial torque: turned to the left for LOW, to the right for HIGH.


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GT L.S.D Pro TT-Model (1.5 way & 2.0 way)
(Time Trial Model)

45° CAM ANGLE
Based on the GT L.S.D. Pro, the GT L.S.D. Pro TT Model was designed to meet the needs of tuning shops dealing with circuit time trials. Its main feature is a 45° drive-side cam angle, compared to the 55° angle used in the rest of the GT L.S.D. series. This provides more mild locking characteristics, reducing the resistance of tire drag (too much effect of the L.S.D.) in circuit running. It is for tuners who are dealing with tire drag resistance resulting from reinforcing the rear suspension member, differential mounting bushing and rear body. The 45° cam angle almost completely eliminates *1 the chattering characteristic of L.S.D.s, reducing unexpected motion changes and increasing stability, allowing it to be used enjoyably on the street. Other basic functions are the same as the GT L.S.D. Pro.

*1 The degree of chatter reduction will vary depending on the oil used, the driver and vehicle condition.

ADVANTAGES OF THE 45° CAM ANGLE
A 55° drive-side cam angle in vehicles with reinforced bodies can result in the inner tire moving in a minus direction during cornering, creating drag which can result in reduced times. By reducing the lock ratio by decreasing the drive-side cam angle to 45°, tire drag during cornering is reduced and circuit times are improved. A lowered cam angle also decreases the power to each plates, providing more stable initial torque.

NISMO's SUGGESTED USERS
CIRCUIT USERS
-Tuned cars with reinforced rear areas
-Tuning shops time trial demo cars
STREET USERS
-Those who want an L.S.D. that is moderately effective on both winding roads and on the circuit
-Those who want to use an L.S.D. in street driving but dislike the chattering

GT L.S.D. Pro TT-model Cam Angles
GT L.S.D. Pro TT-model (Driving/coasting)
Type 1.5 way - 45°/1°
Type 2 way - 45°/45°

GT L.S.D. Series Information (624KB PDF)