Note: I'm talking about RWD cars here.

With open differential, when corning, both inner rear wheel and outer real wheels have the same amount of torque,

whereas with limited-slip differential, the outer rear wheel has more torque than the inner rear wheel,

am I correct?

 

Good question, but how to prove an answer? When cornering on a hard surface with a limited slip diff the diff clutch has to decouple in order to allow both wheels to spin at different rates.. I'm not sure if there is more applied torque detected by either wheel... (?)

 

Torque will end up at the wheel with the least amount of traction. During a typical turn, both wheels have similar traction.

Important to know. The outside wheel travels a longer distance, hence the reason for a differential. All these different TracLocs, Posi, Suregrips do is try to place some friction between the 2 axles so both wheels drive forward.
Place one tire on ice, one on pavement, the one on ice will still spin. With an open or with a limited slip.

 

So how does LSD make a difference? Why LSD-equiped can do a powerslide easier than one that is equipped with open diff?

 

The open will deliver torque to the tire with less traction.

An LSD will try to equalize the torque between the wheels. The type of LSD will determine how efficient it is. Clutch style (like in most production cars) are relatively weak and can handle a lot of torque differential, though some are better than others. Some are strong enough to provide traction in the given example of one tire on ice and one on dry pavement.

A locking differential (Detroit, Loc-Rite, etc.) will allow enough slip to turn a corner, but will lock up if one wheel attempts to spin much faster than the other.

A torsen will deliver torque to the tire with more traction.

 

I have a Tru-Trac rear end and it will slip if one tire is on ice and the other on dry pavement.To remedy the slip,you tap the brake slightly and it locks up tight.

 

A non LSD will have one tire spinning. The other, most likely the outside, will not be spinning hence has full traction maintaining control. A LSD will have both tire spinning so both tires offering no traction in the form of cornering.