Hi Spinnetti.... Well as little as ive been told about Torsen 1 & 2 ... T1's are the origional torsen unit. If one back wheel is off the ground the other wheel won't drive. I believe a T2 if one wheel is off the ground it will still drive like a clutch diff.... Ive read their a bit quieter and us a smidge less fuel.
As you can see... there is a difference in the type of gears inside them.....
I have an '98 LS400 and with to put in a Torsen unit diff centre. Any centre out of a 1995 Mk4 Supra or late model Soarer will bolt straight in but in really after a Torsen 2.... I mean if i'm gunna put one in i'm happy to wait for a T-2
Trouble is their rare and exe.... but i'll wait...... as i want to keep the car till i'm too old to drive.... (I'm 52 going on 21)
haha.. I'm 48'
.. Dunno which I have but its NOS Toyota part. More amazing is that a Toyota company now owns Torsen! Works fantastic. ALL "limited slips" require at least some "reference torque" to work (one wheel in the air=no go). I have 4 Torsen diffs of different kinds and one Clutch style: One in the Lex, one in each of my 2 Audi A4's (center diffs), one in my VW Touareg (center diff I think) and a TRD Clutchpack in my AE86. None of the 5 make any noise that I can hear. The one in the lex makes it understeer a bit under decel (leading me to believe its a T2) but if you stand on it at corner entry where it feels like you are going too fast, it digs in and rockets you through the corner. I totally cut out TRAC once I got that in, as it was worthless (literally cut/welded to remove it totally including the accumulator, secondary throttle etc).
This from the wikipedia (check the torsen site too, explains it all):
1. The original Torsen T-1 (Type A) uses crossed axis helical gears to increase internal friction. The Type I can be designed for higher torque bias ratios than the Type II, but typically has higher backlash and the potential for Noise, Vibration, and Harshness (NVH) issues, and requires a precise setup/installation.
2. The later Torsen T-2 (Type B) uses a parallel gear arrangement to achieve a similar effect. There is also a specialist application of the T-2, known as the T-2R (RaceMaster).
3.The latest Torsen T-3 (Type C) is a planetary type differential, in that the nominal torque split is not 50:50. The Type C is available as single or twin version; the Torsen twin C differential has front and center differential in the same unit.[2]
