Having driven a car with a VZR box, under racetrack conditions, I can confirm that whatever diff the VZR box has in it.. Is a WORLD different and better compared to the standard GTi one..
But I very much doubt its a shitty Viscous LSD.. as I drifted my mates S13 with Viscous LSD, and it was purely shocking.. Power sent to inside wheel and all that, felt terrible.. Much like a standard GTi diff with mucho inside wheel spin when cornering..
It is a world different, a GTi has an open diff. The VZR is definately a VLSD
That compares the VZR VLSD to a mechanical Cusco with clutch type discs.
The VLSD was good when I was driving the Pulsar, but the mechanical in the Silvia is much better other than abit annoying at low turning speeds when the inner wheel skips.