On the Rocks... a Blog: Understanding Suspension Spring Dynamics & Why We Chose Dual Rate - mostly for the pic

Linear vs progressive rate springs | Automotive Thinker - Discussing the finer points of automobiles - for the explanation

Very informative
 

From the article:

Progressive springs are not common in road race cars because these cars typically operate on smooth surfaces. On a car designed for smooth tarmac, these types of springs actually decrease performance as they induce some slop into the suspension.

This is what I noticed with the Swift Spec R springs and why I upgraded to coil overs.

When you think about it progressive springs would require progressive dampening, and getting a gas based dampener to be progressive would be a very interesting feat.

It's what I've been saying all along. Swift spec R will look nice but the true performance won't be there. Stock will be better because of the predictability. How people perceive the "feel" of the car on springs is different from how the car performs...

there is always a give and take. for my Z, ive kept my springs and dampers stock, and just swapped the front bar to make it a tad stiffer. finished her off with RE11's. especially for street driving that is all she needs.

my G35C is another story. she is my dress up car. she is lowered, damped, bar'ed, wheels, s04's, looks, handles, and feels great ... but does that translate to better times on the track? probably not.

Im not going to comment no more loool!! im just going to sit and read :p

This is probably the most logical way for ANYONE here to achieve a very balanced car without sacrificing road comfort. Sway bars would be the only thing I'd add to my Nismo IF I had to add something right now (other than rear camber arms - these cars have too much rear camber).

A sport package or Nismo edition 370Z with a set of adjustable bars, carbotechs (assuming you have 4 pot brakes), and a decent tire will upset a field full of Porche's, and you could still drive this car home.

This sounds like my upgrades...:tup:

Basically what I'm running for now. As skill increases. I up grade.

Hmmm. Good luck with that.

And BTW it's Porsche.

We have always called them Porche's (pronounced Porch) LOL

some dumbarse was calling them porsha

hai undai aiei

Sorry, I missed the "S" - I forget the spelling police are everywhere on the internet.

And yes, the Zs will run with the Caymans and Boxters fine. 911s obviously require some work because they are faster in a straight line, however we can turn just as well or better in some circumstances because the engine is installed in the correct part of our car.

This has been my experience also.

And my wifes as well. The stock nismo is very capable with a good driver. :tup: