Blackline BMW E24,E28,E30,E34,E36,xE36,Z1,Z3 Helical LSD for vehicles fitted with 188 differential.
Suits:-
E24 633csi, 635csi
E28 518i
E28 525i, 535i
E28 528i Manual
E30 325i Manual
E30 325ix Manual Rear
E30 M3
E34 524td Manual
E34 525i Automatic, Australian specification
E34 525i Manual
E34 530i, 535i
E36 323i Auto
E36 325i Manual and auto
E36 328i Auto
E36 M3 3.0
E36 M3 Evo 3.2 with final drive 2227453
E36 M3 USA
xE36 NOT FOR final drive 1428373
Z1 ALL
Z3 M Coupe
Z3 M Roadster
Helical LSD Advantages:-
Equal rotational speed to both wheels
Torque distributed according to traction
Minimal service requirements – no clutches
Quick reaction compared to viscous LSDs
Gentle and progressive engagement, low noise
Easily controlled power take-off and drifting
Gears and body manufactured from 8620 alloy steel
Direct replacement into stock differential
Blackline Helical LSD’s – How They Work
The Blackline helical LSD’s are torque biasing, that is they distribute torque between the wheels, loading more torque towards the wheel with the best traction thus improving performance and driveabitily. Especially in low grip situations.
The helical gearing manages the distribution of friction within the LSD. When torque is applied to the helical gear system it creates force that pushes the gear into the differential body, thus creating friction. Increases of torque, increases the thrust force directly proprotional to the amount of torque. This allows the Blackline LSD to cope with considerable traction imbalance even under heavy power conditions, as would be the case on exiting a powered up corner. But at low torque conditions the LSD can differentiate quietly and smoothly, thus making the differential very suitable for normal road driving. The Blackline LSD uses the popular parallel axis helical geared configuration optimised for even load distribution. They are designed with a torque bias of 5:1 this means that if one wheel loses traction then the wheel with the most grip can receive five times as much torque as the wheel that is slipping. However, five times zero is still zero, so all these helical LSD’s work best when both wheels are ‘planted’ and some traction is still available on the slipping wheel. In practice this is rarely a problem as there is always some ‘drag’ on the slipping wheel, however some drivers expertly use left foot braking to partially lock the spinning wheel.
Note – Helical LSD’s work especially well when combined with modern anti-lock braking systems.