i was originally sold on the gf210's, but noticed they look to be progressive
the nf210's look linear.
can anybody confirm this?

i dont know what to trust.
i read that gf210's are linear, but looking at them i know they are progressive.

cant find any info on the 210's

 

bump

 

Trust your eyes. Tanabe say's both lines are progressive. But as you can see in this picture of a NF210 front spring, it's clearly linear. I can't find a picture of the rear springs, but IIRC they are linear as well. Given their spring rate spec's it's kind of anti-climatic that they've turned out to be linear.

 

anti-climactic?
why do you say that? i am looking for a linear spring actually.
i called tanabe today, and they said rear is linear for both springs.

the explanation was (makes sense when you think about it) to get a large drop in the rear, a linear spring would have to be short, and at full extension you run the risk of it popping out. a shorter shock would cure this but what they do is add a few progressive coils at the top to add length when the suspension is at full extension.

since these coils are softer rate, they get compressed with the cars weight easier and provide the drop of a short linear spring without the danger of it popping out.

i guess if you want a 1.5" or so drop in the rear you have to go progressive, or get custom shorter linear springs, and shorter stroke shocks.

 

Anticlimactic as in not getting into the performance compromises that progressive springs make you live with only to discover that they aren't any stiffer them oem.

And you have the additiional issue of dropping your car 1.2" with ZERO increase in spring stiffness to compensate for the reduction in what is already a deficit in available shock stroke (talking about the fronts). I guarantee that such a setup will frequently contact the bumpstops in the front, even when those stops are trimmed. Sad thing is most that will make this spring choice won't be tuned into what their suspension is really doing so the problem will largely go unnoticed

Tanabe NF210 Series 350Z springs 1.2”/1.2”
Spring rates in LBS 314/353
Stiffer then oem springs by F+0 R+3% (vs 03/04 oem, 04.5+ car's have 25% stiffer rear spring rates)


Finally found a picture I had on had of GF210's, they are very progressive front and rear.



I understand the explanation of progressive rear coils binding presently in place when you compress the suspension to install the bottom shock bolt wrapping up the install. However, is that what is really happening? Most progressive springs on the Z33 have far too many coils to be bound and held captive or inactive throughout the suspension's entire stroke range.