I bought what I was told was a gen IV Auto Trans Supra Torsen Diff -which I was told was a direct swap into the SC300/400 differential. However, when I tried to install the ring gear from the SC pumpkin -the ID of the ring gear was too large and the bolt circle was also too large. It is not enough to be the next size up Supra Diff and so I am beginning to wonder if it was even a Supra diff to begin with. Please help identify if you have the experience.

outside flange Ø = 182mm
ring gear press fit Ø = 126mm
bolt hole Ø = 11.5mm
bolt circle Ø = 160mm

Photos:




It does seem to look amazingly like this one:
http://www.ebay.com/itm/JDM-TOYOTA-SUPRA-MK4-ARISTO-TURBO-LSD-DIFFERENTIAL3-7-JZA80-MK4-2JZGTE-3-7-/261708267413?hash=item3cef073f95&vxp=mtr

 

it looks like a torsen that's for sure, did you boil the ring gear?

 

There would not be a need to. The ring gear is larger. This torsen is supposed to use a smaller ring gear.