OEM springs are linear, except the Nismo Edition 350Z I think has progressives either in the front or rear or both. The Cobb springs are linear as well, it's a noticeable difference between the two types.

Throttle lift and brake dive will be reduced, but nothing like anti-dive or anti-lift kits that are available for other cars (available on EVO and STi).

You also have a nice parts list brewing. My only criticism is that the Koni's definitely add a premium to your cost, factor the koni cost in addition to Cobb springs and you're at or over BC coilover cost which are a better option IMO. I would price out the cost difference between your posted setup and my suggestion (BC coilovers + Cobb sways). If you dont want coilovers, then I would consider just getting Tokico D-Specs, Koni's are only worth it IMO if you get custom valving, so you'll save about $200 with the Tokicos.

With you parts list in mind you may also want to consider getting new suspension mounting hardware (strut top mounts and rubber boots etc), otherwise you have to cannabilize your OEM hardware. Look to add about another $200 if you buy new hardware. I bought a low-mileage used OEM suspension with everything I needed for about $100.

I got all of my parts from ebay vendors clearing inventory, everything minus the locally purchased OEM suspension for less than $600 new! Factor in the suspension adjustment extensions added another $40 I think.

 

hmmm...the rear doesn't look lower at all. Did you take before and after measurements to confirm? Only asking b/c I got bad springs from Hotchkis once that were too long and had to get them to send a second set to achieve the advertised drop.

 

Lots of good info - thanks. I had Konis (SA) on my 97 M3 along wth a mild drop with progressive springs (H&R OE Sport). I loved that setup. I am sure the shocks will help with dive/squat more than the springs. I'd prefer to do it all at once to reduce labor charges. I could look into Coilovers too. As long as the spring rates are not crazy, they shouldn't be too bad.

I could see why the Nismo went to progressive, because the rates (max) went up 35% and it's still trying to be a street car.

Sounds like you did some smart shopping.

I can tell the rear is lower in your pics - 06-08 Z's have 4x4 status rear wheel gap!

The reason I asked for more pics is bacause unless your car is on a perfectly level shop floor, any other surface is subject to eneven height which can make wheel height look different.

I'll have to see if anyone has the sways left.