350z bra

iTrader: (12)

My question is my friend bought some aftermarket springs for his 07 z and i was wondering if they were compatible for my 04 z?

MicVelo

They are compatible dimensionally but the '07 rear springs have a higher rate (fronts unchanged)

Oem spring rates

350Z 2003/2004
Front:314 Rear:342

350Z 2004.5 to 2008
Front:314 Rear:427

The later springs TECHNICALLY can help to make the earlier car a bit more tail biased (oversteer) but in practice, there's not a tremendous amount of difference until you are closer to the limits.

Be aware though, unless you run the also-revised 04.5-08 shocks or go to an aftermarket set, you increase the amount of work your rear shocks will have to do thereby increasing their wear rate.

Also, the revised shock set-up uses a lot less compression damping and fixes a lot of the buckboard ride (bounce) of the earlier models.

Bottom line: if you do go to the '07 springs, consider a shock upgrade.

Mic

350z bra

iTrader: (12)

thanks for the quick reply. My next question is would it be safe to put the aftermarket springs built for a 07 Z onto my 04 stock shocks?

dcains

iTrader: (15)

Did you read Mic's reply?

terrasmak

iTrader: (8)

Aftermarket springs could be many different things, most are modeled after the 03 to 04.5 rates.

Post up what brand springs they are. Also, any aftermarket string will increase the wear of a stock shock.

MicVelo

Safe? Sure. No safety issues but I have to ask.... what is the purpose of all this spring musical chairs? What are you trying to gain?

If going with the aftermarkets, I'd get that... But putting on the '07 OEM springs WITHOUT a shock change, not really sure what you're attempting.

And if you do go with aftermarket springs, don't expect much more use out of the stock shocks.... they just aren't robust enough to handle the increased spring rates for long. Fine at first then they'll eventually die a hastened death due to overheating. (The main reason performance shocks have big pistons and bodies able to dissipate heat better.)

Spike100

If you are asking about aftermarket springs, I assume you are looking for improved handling. As MicVelo and terrasmak mention, you need to consider the interplay of springs with shocks.

Nissan does a good job mating stock springs and shocks. But, if you decide to replace either (shock or spring stock models) with an aftermarket version, be prepared to do some research to achieve an appropriate combination of shocks and springs.

One great resource helping you determine a reliable suspension setup (it might be more than just springs and shocks that you want to replace/add) is here, my350z.com. I would read the Sticky threads first, and then search after that.
--Spike

350z bra

iTrader: (12)

my situation is my friend received free aftermarket non branded lowering springs for his 07 350z. He has no use for this springs and is giving them to me. i want to be cheap and install them making sure that they were compatible with my 04.

RWDBajan

Sounds like you should install them in a bin.

Spike100

It’s not possible to say if the springs are compatible with your 04 350z without knowing the springs specifications (i.e., spring rate, drop measurement, etc.).

One thing I can tell you is that it will be necessary to replace your shocks if the springs lower the car an inch or more. The stock shocks won’t last long with lowering springs.