mine is saying A02B, which means i have a TRD LSD right?
i have found some informations:
The Torsen diff is a standard fitment to all 6 speed mkiv's, alot of the Auto TT's and you'll even occasionally find it on a NA. You can tell if your Supra has a Torsen diff by reading the Trans/Axle code on the Engine Tag which is situated under your bonnet. The last letter of the 4 character code (eg. B03B) denotes the diff type which is "A" for a std diff and "B" for a Torsen diff. The crown wheel on the B series is 220mm whilst on the A series it's 200mm.
The Torsen (TORque SENsing) LSD (Limited Slip Diff) works quite differently to the TRD LSD. The Torsen is a Torque Multipling type of diff with a multiplication ratio of around 5:1. What this means is that whatever torque can be sent to the wheel with the least traction, it can send up to 5 times that torque to the wheel with the most traction. Its biggest advantage is that it can do this extremely quickly and doesn't ever lockup the ratio, but is continuously "sensing" and adjusting the torque between the two wheels. Its only real disadvantage is that when one wheel has no torque available (say it spinning in mud), then 5 times nothing is still no torque to the other wheel, so you can get stuck just like a std diff. Once the car is moving however this cannot happen. See this Torsen Differential Article for a detailed explanation of how the Torsen diff works.
The TRD LSD is a standard type LSD in that it uses clutch packs to transfer torque from one wheel to the other. Transferring torque via clutch packs will be a slower process then the Torsen transfer method and it will absorb more energy from the engine when doing so. However we are probably only talking a few hundreds of a second difference here and maybe a few hp. The main disadvantage of the TRD diff is that it can "lockup" the ratio between the two wheels at 1:1. This means both wheels will then turn at the same speed and if this happens on a corner, it would be exciting at the very least. This "lockup" is also its only advantage over the Torsen diff as even when one wheel is in the mud, the other wheel can provide traction to pull you out.
My personal preference is for the Torsen diff as it usually comes free with the car, reacts quicker and aborbs less power and will never accidentally lockup. However, if you want to go rally driving in your mkiv Supra (don't laugh, there's guys in the USA that do just that) then the TRD would be the better bet.
this means a torsen LSD (with b in the number in the front wing) is better for the track, but the TRD LSD also locks to 100% if nessesary.
correct?