NISMO Anti Roll/Sway Bars Good for Race Z33?
 

Prefer to run light springs and let the anti roll bars take care of body roll, the NISMO alternative is Whiteline but am waiting on them to advise if their 33 mm front bar is hollow or not. If it's solid then that's a lot of unwanted extra front weight, am assuming that NISMO are hollow. Wheels are 18x9 front, 18x10 rear shod with under 100 wear rate semi slicks.

I have the Nismo sway bars. They are hollow and fairly light weight. The ones I have are not adjustable. If I could do it over, I would go with adjustable bars.

I can't see anyone (but there are a few) making solid bars any more since most everyone offers leverage-adjust-torsional rate versus size/density-torsional bars these days. The go-tos (most often mentioned: Eibach, Stillen, Hotchkis. All three of those give a 3 hole-front, 4-hole-rear adjustability covering pretty much every conceivable usage or track condition. Weight is similar on all three.

Nismo are softer in the rear that OEM, I've had both Hotchkis and Whiteline, out of those I prefer Whiteline.

For anyone who wants extra holes in their hollow bar try squashing the ends in a vice to give space to drill extra holes, worked for me using a unknown model OE Nissan bar.

So what I'm gathering here is that the NISMO front bar is relatively soft compared with other aftermarket front bars?

Yes, stiffer than stock but relatively mild as opposed to others out there.

The NISMO S-Tune swaybars are non-adjustable and really not a great option for a racecar. Streetcar, yes.

Based on your statement you should be looking for something stiffer than the Nismo set. But I would just get the hotckis bar if available there, it will take you far before you grow out of it.