great info mate , thanx alot.. i was simply not aware of this mod, did not think it was possible on a VISCOUS slip diff
edit : ah ok, i see what they are doing.. they are changing the diff preload by adding another shim.. not a bad idea, but i recon if you are going to do this , measure BOTH sides and then REPLACE both side shims with thicker, will be much kinder on the spider gears, with the same effect.
an interesting mod for sure..
edit 2 : hmmm... read a bit more, read through the FSM too, not so sure anymore if this is such a good idea.. no matter how you slice it, this WILL change how the gears heel and toe, and WILL increase diff wear.. you might be lucky and it lasts some time, or not..
in the one thread you listed there is actually one guy that did it right.. he removed and cut open the viscous clutch pack , and replaced the silicone oil with the thickest he could find, then welded it shut again..
see about middel of this page, posts by "bauerpower"
http://www.skylinesaustralia.com/forums ... e__st__140