I have been searching on lowering springs and have decided that (for what I am looking for now) the Z springs would be perfect. Just enough of a drop to notice, but without having to replace shocks and worry about camber issues.

However, I did not find any reference to their use on '05s or on sport suspension equipped coupes.

Does anyone have any insight? Thanks

 

I thought I just read Gsedan35's post on another thread that the 04+
350z uses higher spring rate on the rear, so unless you have the 05 coupe
sport sus with the stiffer dampers, you might want to look for 03 and
350Z springs. (?) I recommend you send a PM to Gsedan35 concerning
those springs.

 

Here's a total run down on oem spring rates and drop amounts


2003 oem 350Z springs 314/342
2004 oem 350Z springs 314/342
2004.5+ oem 350Z springs 314/427
2004+ oem 350Z roadster* springs 314/427

2003-2005 G35 coupe all car's delivered from the factory with oem 17's or 18's regardless of build year 314/342
2005 G35 coupe when delivered with oem 19's 314/427

2003-2005 G35 sedan without sport suspension 238/308
2003-2005 G35 sedan with sport suspension 314/342


If oem 350Z springs are run on a G35 coupe you will get a 1/2" drop
If oem 350Z springs are run on a G35 sedan you will get a 1" drop**
If oem G35 coupe springs are run on a sedan you will get a 1/2" drop***

Notes
*Unlike 2004 350Z coupes where midway into the model year Nissan revised the suspension, all 2004 roadster's have the revised suspension and all have the higher rear spring rates

**Some G35 sedan owners with oem 350Z springs have reported getting less then 1" of drop on the rear. On my own car I got a measured 1" front and rear

***As measured on a sedan that I helped install oem coupe springs on.

 

Gsedan35 - Thanks for the very informative reply.

Based upon what you are saying, if I use 2004.5+ OEM Z springs on my 2005 coupe (wi factory 19's) the spring rate will be the same and it should result in a 1/2" drop front and rear. All things being equal, ride quality shouldn't be sacrificed at all.

Thanks again...

 

I'm interested in probably lowing my coupe about 1/2 inch also (front bumper already scraping), so where is everyone buying their OEM Z springs from? Nissan Dealership?

 

I think justin over at www.everythingg35.com can probably get a hold of those
Z springs.

man, so many different kinds, hard to keep track of which is which.

 

I picked up a set of rather new 2005 oem Z springs on my350z.com for $50 plus $15 for fedex ground. If you look a little bit in the classifed section their, you will find some post's where seller's are offering to sell, maybe a page or so back.

 

Jim, can you speculate on the reason Nissan would up only the rear spring rate significantly? From 342 to 427 is almost a 25% increase.

 

Gsedan35 - you appear to be an authoritative source on this issue, so I'll ask you. When going from a sedan w/sport or 6MT, to an oem z setup, some people recommend also replacing the stock shocks, while others don't. What is your recommendation?

There are a couple of 03/04 g coupe owners in my local group that have their oem springs that are willing to just give them to me. Other than a drop, will I see any handling improvement whatsoever? Can a 1/2" drop, with identical spring rates, really yield much difference?

 

I think a lot of owners of the 03 - 04 Zs were saying that the rear of the car was somewhat bouncy and pogos over dips and stuff. So I would think stiffer rear springs would not allow the suspension to flex as much alleviate the bouncy feel.

 

Well even if you don't go to a higher spring rate, the sport suspended shocks on the sedan are underdamped period. I know this for a fact after back to back driving on a technical road course. Both cars were '04 6MT sedans. One had stock sports suspension, the other had an oem '03 350z suspension. So if you're going to switch out your springs for coupe springs, might as well put them on superior Tokico D-Specs or Koni Yellows. No point really in sticking with the sedan sport shocks unless money is a big concern.

 

That's really hard to say, may boil down to the most cost effective way to get that they wanted as part of the revision, to address complaints about the 2003 oem 350Z's ride quality.

 

You can get away with running oem sedan sport shocks with oem 2003 350Z springs, I ran them for awhile to test this out. It would certainly be better to run Tokico D-spec's instead. The rear shocks just aren't totaly happy and not running them does kill off some floatyness that is more noticeable as speeds increase.

A 1/2" drop will help, but your not really going to get in the car after installing them and notice a change very quickly. But for free, heck install them yourself why not.