Chris, have you tested both bars? Whiteline and Hotckiss?

I don't see how a solid 28mm bar could possibly be less stiff than a 35mm tubular.

That's if they're made of the same alloy using the same process and are both tubular or solid.

That matrix doesn't say anything about going from tubular to solid or vice versa.

It depends on the wall thickness of the bar and the shape of the bar, it's not just about thickness (shape restricted by stock end-links). I haven't used the Whiteline so I'm just going by the spring rate data I could find which could be wrong.

A tubular design of 35mm roughly translates to 32mm solid.

I couldn't find any spring rate data on the Whitelines, unfortunately.. Did you find some?

Thanks for the info though, can never have too much knowledge.

The Whiteline is not between the Eibach and Hotchkis. The Eibach front bar is stiffer and lighter than the Whiteline.
http://www.the370z.com/attachments/b...ars-sways2.jpg

It is stiffer than the Stillen though.

The Eibach is much thicker than I first thought, thanks for the numbers.

The spring rates for the Hotchkis rear are:

930, 1160, 1490 lbs/in (based on the 28.5mm bar)
+70, 110, 170% stiffer than stock 370Z

The Eibach rear sounds crazy stiff if their numbers are accurate.

I tried the Eibach front bar for a few events last year. I'm running 285 RE-11s all around. The Eibach bar on the stiffest setting made the rear very squirrelly...lots of oversteer. I went back to the stock bar and have been happier and faster. Really, it's driver preference, most of us here can't drive the car to its capable limits and Whiteline, Eibach, or other won't "turn" us into a pro.:driving:

I'm on the fence between this and Eibach, mostly because Eibach is a trusted name.

Would you consider RE-11s to be a goo match for it, or should I look at something more aggressive? I'd like to fine tune the suspension through this current autox season, possibly adding springs into the mix.

I think the Eibach bars are meant to match with their springs as well. Not sure though.

If you are doing springs, you might as well do Coils since it will move you into ASP class either way. RE-11's will perform well once everything is dialed in. I'm on 18" wheels and the RE-11's only come in a 275 tire which I want more meat....

Let's just remember that in order to be competitive in ASP you're going to have to run something on par with Hoosier A6's.

Also I thought the non-Nismo Z's were able to run in STR now. Not sure what the STR rules allow for suspension changes and what the max tire widths are but it might be worth a look.

We have a 350z here that competes in STR but max tire width is 255 and max wheel width is 9.0". If running on Base wheels, it could be worth it. Looks like basically the only thing holdin us back is the skinny wheels and tires lol. Here in Hawaii, there's only 1 other car in ASP with me so its not tat big of a deal and hes running on Direzza's. I'll be fine on my RS3's lol.