I've read a million threads on people trying to run the S15's helical type LSD in their R200's without success. This is due to the fact that our current output shafts are 29 spline 30mm, whereas the S15's HLSD uses a 30 spline 31mm.
The S15 HLSD's though are awesome - I had one in a 240SX race car - and cheap - can be found with the correct output shafts for around $550 shipped. Much more cost effective than a Quaife.
Here's one idea that I haven't seen anyone try; is there out there an adapter that goes from the 240SX output shaft - its a 6 hole in a triangle pattern - to 280ZX CV shafts or even to the stock stub axles? Instead of messing with spline counts and shaft diameters, why not try to bolt up the S15 shafts to our existing rear axles? Modern Motorsports has conversion kits to go from the existing Z output shafts to other modern CV setups; why not go from the 240SX bolt pattern?
I'd love your thoughts.
The 240sx output shaft connecter bit looks like this... its the one on the right.
http://importnut.net/240pics/LSDswap/DSC02077.JPG