I am looking for a spring that will work great with the stock components(mainly shocks). Any recommendations?RS-R spring?

 

eibach pro kit

 

is that to big of a drop for the shocks?

 

RS-R

 

Do i need to replace the front struts/shocks when i throw my eibach pro kit on, if so what brand/style.

 

If you've got an early '03 Z with the funky damping rates, you'll want to dump those shocks when you do the springs. You won't know just how badly they suck until they're gone!

I chose the RSR springs based largely on the spring rates, which are both linear and stiff enough to make a real difference but not enough to be punishing on real roads, and are biased (10%:22% over stock, or 12%) toward the rear, which pretty much dials out the Z's tendency to understeer. Many spring sets I looked at were spec'ed stiffer in the front, which just didn't seem proper, and the coilovers I considered were stiffer than I'd want on the street.

My sways are set to a similar (32%:45% over stock, or 13%) rear bias, and the combination works really well. My Z corners flat, launches cleanly and feels a lot lighter than it is. Reminds me a lot of a Porsche without the trailing-throttle scariness.

 

You might also research the Hotchkis TVS I suspension kit. It includes springs and sways and really makes the car handle well and ride much better than stock. Contact Greg at GSC, one of our sponsor/vendors and chat with him about it. He will also give you a killer deal on the set. I paid well under $400 shipped to my door for the kit. Great product and killer price. Hard to beat that!

Oh, can you tell that I'm really happy with this product!

 

I'm looking sell my eiback pro kit. Just picked up some sustec pro coilovers. If interested, drop me a line. as for the toe ajustments, I have kinetics arm adjusters for rear as well for sale.

 

what is the drop on the eibach
pro kit?how do the rsr springs vs. the tvs springs compare?

 

best spring on the market right now for the 350Z with stock shocks is the Hotchkis. The springs will remove the bounce in the suspension and inprove ride quality. They actually lower the spring rate on the hotchkis where as the Eibach kits all add 10-15% spring rate causing the bounce to get worse. If your going to go with the eibachs I would suggest a set of Koni Yellows also to keep up with the increase spring rate.

 

what do you think about the RSR springs?

 

100 times better than Hotchkis, especially RSR Ti2000

 

I have the RSRs, and I must say they ride almost like stock. I could feel the hanldling tightening up a bit but not as dramatic. Then again, these are just springs so that's all one would expect. The drop isn't too low either.

 

PICS???

 

thank you for all the help

 

Why? Do you have comparative data? Have you had experience with each setup?

I have Hotchkis TVS and can say it works well and I'm happy with the setups performance and delivery of claims. Can I say they are the best, no. I don't have that type of data to back it up. I think we all have to start being more realistic with our claims. As this board and automobile progress and mature we need to start working with facts not emotion or the "I have it so it's the best" mentality.

Just my $0.02....

 

good point

 

RSR 350Z springs
345/417 F+10% R+22%
Transfers +12% roll stiffness to rear

Hotchkis 350Z springs
340/330 F+8% R-3%
Transfers +12% roll stiffness to front

Hotchkis's tuning methodology was done because they see the rear shocks as to weak to control the oem spring rates on bumpy surfaces. I rarely find that type of road surface when I am pulling G's. The only claim the company makes is this nets a reduction in slalom times, no claim is made on steady state cornering or lower lap times. However, in a which is better , the RSR springs are better. It is a tuning fact that roll stiffness transfers are done to change at the limit behavior. Adding more to the front will increase understeer on a car that already has it. Moving roll stiffness to the rear will reduce the Z's natural bias to understeer. Furthermore, sway bars are NOT meant to compensate for poor choices in front to rear roll stiffness balance, they are meant to fine tune a already properly dialed in chassis.

Both springs also bring two pluses to the table, neither drops the car so much as to compromise suspension travel and both do not have progressive spring compromises/liabilities.

In conclusion, ultimately aftermarket shocks offer superior dampning control, no matter what spring your on. And one would be wise to replace the oem shocks no matter what your priorities are. Accepting a performance compromise for the sake the oem shocks isn't something we should let ourselves fall into given what you have parked in the driveway.

 

The progressive nature of the springs is Eibachs compromise on ineffective oem shock dampning Having reviewed a vast amount of owner comments from 350Z owners with Eibachs. These reviews show owners reporting improved bounce control with the Eibach springs. I have never seen a Eibach owner post saying the springs made the bounce worse. They have never said the springs killed all the bouce off, however. It's fresh in my mind having just searched Eibach posts on another matter going back to when the springs were introduced.

Eibach's spring rates to oem are as follow.

Eibach 350Z progressive springs
296/384 front 316/421 rear
F +22% R +23% (looking at peak rates only)
Spring stiffness to oem as seen in a right hand corner (reverse for a left hand corner)
RF-6%
RR -8%
LF +22%
LR +23%

 

Good answer GSedan................

In my case I face an urban scene where many city roads and highways are bumpy, patched roads. I find the Hotchkis delivered the goods in my environment. Especially since I didn't want to spend on replacement shocks at this time.

So in the end you need to do research and get a product that is best suited to your environment and goals. Hopefully the folks in the know on this board will continue to come forward with facts to assist the reast of us in our projects.