LSD NEWS!!!

[hondacivicsipower]

Well, I was curious about lsds, and I asked on this site, but couldn't find any help, so I searched the net. This response is far superior, and should be the final answer to questions about clutch type viscous type helical, etcthanksand enjoy

As the name implies, it is designed to limit slip... it does this by using a secondary mechanism to transfer power back to the slower wheel when a large difference in speed exists between the wheels. There are several ways to accomplish this transfer, and the most common types are the clutch-type and viscous-type LSD.

Viscous-type limited slip differentialsA viscous-type LSD uses a thick fluid sandwiched between plates, one plate being connected to (drives) each wheel. When a rotation difference occurs between wheels, the faster plate spins the fluid which in turn spins the slower plate, hence transferring power from the faster wheel to the slower wheel. A viscous-type LSD has the advantage of requiring little to no maintenance, since the fluid never wears out. However, from a performance standpoint, a viscous-type LSD is not ideal. On a viscous LSD, it takes a split-second for the LSD to react to slip as the fluid must speed up before it starts turning the slower plate. On higher horsepower cars, any lag in response resulting in uneven traction is especially undesirable.A viscous-type LSD is often used as the center differential on AWD cars, where the delay in the transfer of power (from front to back) is not as critical. It is also often used in OEM applications where cost, ease of maintenance and quiet operation is important.

Clutch-type limited slip differentials A clutch-type LSD uses a set of clutch discs, that are connected to each wheel, and the discs are clamped together at a certain pressure when in operation. When one wheel tries to rotate faster than the other wheel, the clutch discs start to slip, the faster disc transfers power to the slower disc through friction, hence transferring power from the faster wheel to the slower wheel.A clutch-type LSD responds immediately to any slippage, unlike the viscous-type LSD, and is so better from a performance standpoint. A clutch-type LSD is also much more easily upgradeable to handle high horsepower, as the number of clutch discs can be easily increased or the clutch disc sizes can be enlarged. Most aftermarket clutch-type LSDs have larger/more clutch discs. The downside with a clutch-type LSD is that with the slipping of the clutch discs, they eventually wear down and will require maintenance. Also clutch discs will chatter when they are engaged, so a clutch-type LSD is not as quiet as other LSDClutch-type LSDs are often offered as 1-way, 2-way or 1.5-way. A 1-way LSD only engages the clutch discs only on acceleration, while a 2-way LSD engages the clutch discs on both acceleration and deceleration. If the clutch discs work to limit slip on deceleration, they can optimize traction under braking, but at the same time as they transfer power from the faster wheel to the slower wheel, this increases oversteer in turns. Therefore a 2-way LSD is generally considered more difficult to handle, but superior for handling, while a 1-way LSD is more forgiviing. A 1.5-way LSD is a compromise between a 1-way and 2-way, as it engages the clutch discs with less pressure on deceleration, which allows for more slip on deceleration and hence less overstee

Gear-type limited slip differentialsFinally there are other limited slip differentials that work through gears to limit slip. These LSDs can offer very immediate response like a clutch-type LSD, with little maintenance and quiet operation. However, there are not as easily upgraded for high horsepower as with the clutch-type LSD, they are limited by the strength of their gears. Gear-type LSDs are also generally a lot more costly than the clutch-type or viscous-type LSDs.

[onosqv]

Thanks for the summary and putting it all in one place, but all of this info can be found via SEARCH :-D.

And why read, when you can have animations & descriptions:

http://auto.howstuffworks.com/differential.htm

That's a link provided from the sticky in the Tire,Wheel, Suspension forum.

[Bronze MFP]

are gear type LSD's offered in 1/1.5/2 way? which is the nismo helical LSD?

[S13 Charlie]

No, they are inherently different from clutch diffs, in their operation. The method in which gear-diffs (a la HLSD) transfers torque is dependent on the gear ratios in unit. Therefore, they can't be rearranged for 1, 1.5, 2 way etc..

Check out Howstuffworks.com and look for the differentials page. Very informative.

Cheers,

C