Okay I edited my post because I anwsered my own question typing it out, I guess my question now is the LSD is inside the bell housing right? So I cannot actually check if it has a Torsen like the guy said ?
oh torque biasing differential. idk why i drew a blank on that.
hopefully someone with a torsen will chim in. i know the stock one has a rod threw the diff. not sure if the torsen unit has one or if its different. then you can just pull the passengers axle and look in the diff.
only other way is like put one wheel on gravel (or something low traction, grass, ect) and the other on pavement and floor it if you get spin on the pavement you got yourself a nice diff. if it only spins in gravel, the guy who sold you the car will probably have you wanting $700 back so you can go buy the diff
You can't jack up the car and turn the wheel to see if it has a torque biaisng limited slip differential. The TBD works by giving a ratio of the power to the wheel that has more grip than the other. Problem is when one wheel has no gip, the power will go to it since it is higher than the toque bias. If there is no available torque on one of the wheels, the diff acts as an open differential. That also means that putting one wheel in gravel and one on pavement won't help you tell if you have a TBD or not since the differnetial in grip is most likey larger than the torque bias ratio. If the car clutch pack LSD, then both wheels will turn because of the preload in the differential. When a clutch pack or salsbury LSD has slip on one wheel over the other, the center part of the differential has ramps that it rides, aplly more force against the clutch packs making the to wheels spin at the same rate. The larger the difference in torqu, the more force the ramps puton the clutch packs. You can tune these differentials by adjusting the ramp angles, the number of clutches in the diff, as well as changing the preload. Here's what wikipedia has to say on how a torsen torque biaisng differential works which might make more sense.
"The Torsen differential works just like a conventional differential but can lock up if a torque imbalance occurs, the maximum ratio of torque imbalance being defined by the Torque Bias Ratio (TBR). When a Torsen has a 3:1 TBR, that means that one side of the differential can handle up to 75% while the other side would have to only handle 25% of applied torque. During acceleration under asymmetric traction conditions, so long as the higher traction side can handle the higher percentage of applied torque, no relative wheelspin will occur. When the traction difference exceeds the TBR, the slower output side of the differential receives the tractive torque of the faster wheel multiplied by the TBR; any extra torque remaining from applied torque contributes to the angular acceleration of the faster output side of the differential."
Usually you can tell that you have a TBD is that under medium to heavy throttle mid corner, the car will actually turn harder into the corner towards the apex. It took a few laps around the track in my spec neon with a quaife to get used to being able to apply power to the car mid corner unlike my jetta or Focus which both have open diffs.