lsd tranny what does it actually do? does it kicks in when you need it or does it work all the time? i heard so many story about what it actually do, but still not sure how it actuaal work. i thought it was to make both your front wheels spin insteand on just one, but if this is true hope come i get different air psi after runs? could someone please explain.

 

The differential is a set of gears in the transmission that allow the driven wheels to turn at different speeds. This is necessary if you wish to turn.

Now most stock differentials are called "open" differentials. This means that they allow the wheels to turn almost entirely independant of each other. A side effect is that under conditions in which traction is lost all of the power is sent to the wheel that is already spinning out, thus you have the undesireable result of not going anywhere, or at least not going anywhere fast.

To solve this, the "limited-slip" differential was developed. Now there are different kinds of differentials that have mechanisims that allow power to be transmitted to both driven wheels under heavy acceleration, but calling them all "LSDs" is a misnomer. A true LSD uses a set of clutches that lock the driven wheels together while going striaght, but allow for some slip while turning so that the outside wheel can turn faster than the inside (which it must do). Hence the name "limited-slip."

Another traction-enhancing differential design is the Torsen, which is what the ITR comes with. Torsen stands for Torque-Sensing. The Torsen is actually a step better in that it applies more power to the outside wheel when the car is turning. It is a gear-based unit, similar to the Quaife (which is called an ATB, or Automatic Torque Biasing differential). The extra power sent to the outside wheel helps the car corner better in some situations. It is still a mechanical system of gears though, and does not "kick in."

The only system I know of that actively "kicks in" is Honda's ATTS, found on the Prelude Type-SH. This differential uses clutch packs, but is controlled by a computer. Its purpose is similar to the Torsen and Quaife in that it applies more power to the outside wheel under cornering. The performance difference is that this is its main purpose, not traction under acceleration like a traditional LSD.

 

so what your saying is that is only helps when turning? is if going staright it does nothing? thanx for your response..

 

Everything about an LSD can be explained here: http://www.howstuffworks.com./differential8.htm

 

Nice link.

 

is the ITR OEM LSD compatible with a B16a tranny? can i add it to that specific tranny?

 

Yes and no. It will work fine, but you have to replace the ring gear (and counter shaft) with B18C parts.

 

so it would probably cost less or the same if i got a Quaife unit specific for the b16a?

 

It would be cheaper to go with the Quaife unit for the B16a. The two LSDs are priced about the same. I believe ring gears go for around $200, so the Quaife is definately better in both price and performance.