New to Z's. I have a completely stock 08. I had the chance to track it a couple of weeks ago on 17" DOT's (thanks to LAZE1) and my 18" Conti's.

I have an idea of where I want to go with the suspension. I'm just confused by some of the aftermarket options.

My understanding is that the stock rear spring rate was raised from 342lbs/in to 427lbs/in for the 05+ models. In looking at aftermarket springs, most are showing the same rates for all models 03+. All the springs I've found so far would increase the rear rate for the 04- models but would represent a .05% to .25% decrease in spring rate for the rear for the 05+ models. Not exactly what I'm looking for.

Does anyone offer custom spring rates? Also, does anyone know why the rear sping rates were raised and if anything else was changed.

TIA
Mike

 

You can get any rate you want from Eibach...

I have 650's in the rear of my car...on DA Koni's.

 

I run 671 lbs 12K springs all around