if you want to improve yoru suspension... change your struts and springs.. get some sway bars and change all your bushings... then get a strut bar...

 

You can get a strut bar from Cusco. They used to make a rear, but I don't know about now. Z's are pretty much nostalgic cars in Japan and most people don't deal with them anymore. racetep.com also sells a strut bar, but their service is questionable and not everyone says the bar fits.
John 82ZXT

 

I got the triangular strut bar, it didn't fit and they ignored me when I asked them about why it came all screwed up!

Luckily I knew someone that helped me cut the one end off and re-weld it. The thing already looks like a home-made bar. Don't buy from Top End Performance (racetep.com), weld your own!

 

im making my own out of the spare sway bar that im getting

 

No, not a lot of work. My dad really did all the work. He has the welder. The welds were not as neat as the other welds, but I cleaned them up as best i could. I really should take it off and re-paint it.

I bought longer bolts for the rear mount; stainless to be exact. They are the two bols that hold your hood latch on. You'll have a tiny bit of slop in the bolt holes that allows for some adjustment of how the hood latch latches.