The stock rear brakes are fairly good, a large (for such a light car) 8" x 1.75 brake shoe. Make sure the brakes and clean and adjusted correctly. Using a performance pad will improve it.
But for coolness sake... read on.
Pitroad rear disc adapters for B110
- Uses late model S130 (280ZX) caliper and rotor (I think it says it uses Skyline HR30 adapters)
Andy: The Pitroad rear disk brake kit only includes the brackets, E-brake cables, axle sleeve thingys, clips, rubber brake hoses, and axle bolts. You supply the calipers, pads, and rotors from an 82-83 280ZX, as well as new oil seals for the axles, wheel bearings, etc. It's pretty straight forward, you have to pull off the old drum brake assemblies and put on their new bracket just before you put the new wheel bearings in. You do have to drill two really small holes on the E brake cable holder, but other than that it's really easy.
In general, 1982 280ZX and 300ZX has a smaller rear caliper with larger pads than the early (1979-1981) 280ZX. The offset of the early vs. late caliper is quite different.
82-84 Maxima use a conversion plate to bolt a rotor to drum-brake rear struts. This might be useful in a swap. Details: Z Home