On a car that's not running aero, slightly lifting an inside front wheel is OK as long as the car isn't pushing out of the corner under power. For a compromise street/solo car I've often went with what many people consider really stiff springs. What makes them work on the street are shocks with great rebound control and a soft compression setting. Digressive valving helps even more.

 

If they are progressive, the claimed rates are maximums.

 

Yes, thats "IF" of course and I alway's do use that disclaimer whenever I discuse progressive spring rates. But they are not progressive, no matter what Tein says. They do not have coil bind nor do they differ in wire diameter top to bottom, they are linear springs.

 

And the stiffer springs will help make up for setups that are short on bump travel, though a better choice would be the same with shortened bodies, ala Truechoice phase 4. Though my own experience was that off the shelf Koni sports with 448lbs in the front did not have rebound control in reserve, going even higher in rate would not extend things.

Curious in my neck of the woods, 500-600 lbs in the maximum I can use and still maintain tire contact 95% of the time. When you mention "really stiff rates" for this platform what does that mean to you? Again, only asking because I'm curious.

 

That's right your running the Truechoice coilover setup. But I didn't know you were running Koni yellow's and revised rear springs. I just got a email yesterday from Truechoice about the cost of buying 2 front Phase 4 shocks. I'm basically thinking of the same setup with yellows in the rear on revised oem rears. Thinking that the front rate will be either 500-600. Glad to hear you like it. On the front shocks, which phase of kit are they from, III or IV?

 

I agree about the Tanabe spring rates, the only thing that gives me pause is how they may be tuned valving wise and how you cannot adjust them. Based on the one or two owner review's ever posted on them since most G and Z boards got started, I got the impression they they were valved more towards comfort then performance.

On the Stance setup, I've been considering them or thier 3-way adjustable setup. As far as the noise in the rear, if you don't mind giving up the ability to adjust rear ride height thier is a very simple effective solution. Do not install the rear springs the kit comes with, run your oem rear springs, math's out to be about the same wheel rate in the end. You can modify the upper oem upper spring seat to lower the rear of the car, up to .8". I I were to get them, I'd run the rear springs just as I've suggested.

 

I'm running Dspecs with 06 Z fronts (5 turns from firm) and 05 coupe rears (4 turns from firm). My car unsettles quite easily around Chicago. On a few roads the rear wants to jump to one side or the other.

I want to get this resolved, maybe a new setup is in order.

 

So the noise issue will be solved if the I used the OEM location? I'm not going to go lower than an inch and I really don't care about the height once I have it right. Thanks and keep it up Gsedan35, you provide lots of suspension information for everyone!

 

Also, using the oem location means that there will be no springs on the rear shockbody, correct?

 

Well my main concern revolves around the rear oem lower shock mount bushing being unable to deal with the the forces that a true coilover brings to bear on it. That is the source of most all the rear noise issues I have read about with the Stance coilover. That however, doesn't mean I could have missed post's that talked about a noise issue that originates somewhere else, I haven't found them though. Getting a sperical bushing made and pressed in would solve the problem, but none are on the horizon that I'm aware of. Beside's I've run the rear spring setup that way with a .8" drop and been very happy, though it's possible once the car get's on the scales for corner balancing I may not stay so happy since I wouldn't be able to adjust in the rear.

Correct.

 

Ok, so back to Konis.
I was doing some research about the truechoice set-up.
Anyone know how much it takes to get the front converted?
And would someone have problems with the shock running out of travel in the rear with the revised springs?
I am considering the truechoice set-up but I just wanted to know if this will get rid of the shock travel problem and if someone can enlighten me on some details, it'd be very helpful.

 

I'm just running the standard sleeve and race spring conversion.

The REALLY disappointing thing about Truechoice is that their sleeve kit, at its lowest setting, brought my car *up* to OEM ride height. The Koni was already at it's lowest ring.

That's why I got the front rebuilt. They were going to charge me $60 to machine new grooves in the body (plus to and from shipping of course) - but they would do it for free if I got the dampers rebuilt. Pretty disappointing that I had to pay extra to compensate for their lack of R & D.

I did get the dampers rebuilt and was charged an extra $25/damper over the standard rebuild cost for 'extras' I never requested. Knowing I'm running 500 springs up front, it's possible they upgraded my dampers to one of their own Phases, but it was still very unprofessional in how they handled it. To top off my disappointment, the freshly painted body (included in the standard rebuild cost) chipped when the one dampers standing upright accidentally slid flat onto the concrete floor. Frankly, my kid smashes his $1 Hotwheels car together daily and they don't chip anywhere near that easy.

The kit is really well made, but it appears from my situation, they hadn't done their homework in making sure it worked well with the 350z. All they have to do is machine the internal race/perch within the threaded sleeve about 1" higher and it's perfect.

 

I don't know yet, I haven't done the math or really any suspension tuning on my 350Z (I just finished putting the Nismo R-Tune LSD in the car.) The T2 springs are around 690 lb. in. and I think that is probably a reasonable starting point for a track car. Some have said that its too stiff for a street car but, even at 47 years old, I prefer a pretty stiff street ride. I'm probably not the best person to offer an opinion about a dual purpose car.

 

What did Truechoice do to the shocks? Install sleeves and a Tophat?