New here... i did a couple of mods to my car, and i wanted to get springs next. I'm having trouble on picking a certain brand. I hear Eibach and Tein are good. Any advice?

 

Most springs are picked based on drop amount's with little regard to how they may effect the dynamics of the car in regards to at the limit behavior or maintaining the "sport" part of how the Z is a sports car. That said, many aftermaket 350Z springs are a compromise to live with the shocks that Nissan used to use on the Z, your 2005 car has revised shocks and offer up much better behavior so you have less of a need for a spring that is designed around this compromise. Even so, you will still benefit from aftermarket shocks.

The following springs come to my mind. I have adjusted the stiffer or softer to oem specs to reflect that you have a 2005 Z (your car uses stiffer rear springs then pre 2004.5 cars)


RSR 350Z linear springs .6”/.6” drop on 350Z
Spring rates in LBS 345/417
Stiffer or softer then 2004.5+ oem springs by F+10% R-2%

Hotchkis 350Z Linear springs .6”/.8” drop on 350Z
Spring rates in lbs 340/330
Stiffer or softer then 2004.5+ oem springs by F+8% R-23%

Tein H-tech 350z linear springs .3”/.2” drop on 350Z
Spring rates in LBS 358/375
Stiffer or softer then 2004.5+ oem springs by F+14% R-12%

Swift 350Z linear springs .8”/.6” drop on 350Z
Spring rates in LBS 336/364
Stiffer or softer then 2004.5+ oem springs by F+8% R-15%

 

I just installed (yesterday) Tanabe springs on my 03' G35 sedan. 1.5in drop in the front, 1in in the back.

I like them because they lowered my sedan, without overdoing it!
Everything seems to be alot tighter than before. I can realy feel a diffrence!
Good-luck,