What's up fella's? So i've had my car now for a couple years and finally decided to lower my ride on some Tein S-Tech's. I have a 05 Z with the revised stock suspension, and man did i notice a huge amount of oversteer with the S-Techs in comparison to the stockers!! On the daily grind, the car does feel a little more comfortable and looks more aggressive, but i really can't get over this oversteer... I didnt really notice it until i took it to the skidpad and felt like i was driving a completely different car!!! This thing went wild on me.

I was wondering if anyone else has noticed this when swapping out their springs for S-tech's or any other lowering springs? What could be done to counter this effect? I do enjoy messing around on the skidpad from time to time so i wanna have a nice looking drop that is functional as well. any suggestions? Im thinking D-specs?

thanks in advance,
Carlos

 

New Bridgestone RE760 on all 4
Front 255/40-18 on 18x8 45mm
255/40-18 on 18x9 38mm
Front sway Hotchkis set med
rear sway 350EVO set to med
Tein 350Z S-tech
Revised 350Z shocks

VDC on = electronic nanny stabs the inside front brake pretty early

VDC off = extreamly balanced at the limit of adheasion, can roll into throttle when I want coming out of the hole. No oversteer issues to report at all

What are your alignment settings post drop?

Also, tire condtion and what sway bars and settings on them?

 

Need more info as mentioned.

 

@Gsedan35 Correct me if I'm wrong, but aren't your front tires taller than your rear? This throws off the VDC.

My reasoning is since you are using 255/40 on fronts and rears, and your rears are wider, essentially it makes the sidewalls not as tall for the rear. Perhaps you should use 245/40 front and 265/40 R or go use a tire calculator to figure out the measurements.

 

His front is a hair taller, but ........ The G35 sedan that he drives (same suspension as our Z, just longer wheelbase) comes from the factory with equal height tires, equal height is what his computer is looking for. Running a big stagger in height like we would on a Z or G coupe would throw off VDC if he has it.

 

Sorry. Currently im on the stock revised struts with S-techs.
Stock sways front and rear
Falken 452's on all 4 tires- basically new ~10k on them
245/40/18x9- fronts
285/35/18x11- rears

i'll post my alignment numbers tomorrow when i get a chance. But as you can see, the car's suspension is basically stock, just have wider wheels...

 

Your tires and wheels are very similar to mine, but I have different shocks, SB and springs (see my Sig). My car is PERFECT now. I did experience oversteer when I had MUCH stiffer rear Nismo S tune (500lb) springs, which I swapped for softer ones (Eibach Pro Kits).

I'm surprised you now have oversteer with NO OTHER changes than the S techs. In fact, I would think it would REDUCE it, since the S techs add more spring rate up FRONT vs REAR as compared to revised stock set up.

Tein S-tech 350Z springs .7“.6“ (fronts are slightly progressive, rears are linear)
Spring rates in LBS 386/402 (estimated front intial rate is 327lbs)


STOCK
2004.5/2007
314/427

Of course alignment would be the FIRST thing I would look at and rule that out. If you still have oversteer problem, then try stiffer front sway bar next..leaving rear alone. Also, make sure shocks are in good shape.
Good luck.

 

^^ honestly, thats what i was not getting about the whole situation. I mean i guess what i could be feeling is the effect of the fronts being PROGRESSIVE and the rears being LINEAR? maybe these springs are allowing for a little more body roll in the front because of the changing rates in the front vs the constant rates in the rear? I really have no idea, but all i know is that my "driving dynamics" have really changed...

Before it took a little effort to lose my back end coming into corners (TCS OFF) but now just slightly too much gas entering a corner and i feel my rear end kick out (TCS OFF)

I've drifted my car for a while now, so it's not to the point where i can't handle it, but it gets annoying...

 

Fronts don't look *that* progressive in this pick below. The closer coils will basically collapse together when on the car..rendering them null and void as far as rate effects. So,I think the actual potential rate change (progressive range) is pretty tight in this case.

 

I hear ya. As i said, this was just an observation and was asking on some opinions on what could be done to maybe cure or lessen the effect....idk what it is, **** it might just be my imagination messing me up cuz i know i have progressive's in he front lol

Do u think some D-specs would be a nice addition to the S-techs? im debating purchasing a set or saving up a couple hundred more and getting coils and calling it a day...

 

D specs are very good, but for another $500, you can get Eibach Coil Overs (OEM style rear), which are actually KWV1s. Those are not rate adjustable like D specs. Unless you go the *Megan* route..which has it *all*, but are lower quality.

 

You would be better off with S.Techs and D-Specs than with Megan coilovers.

We still don't know what happened to your alignment. Awaiting numbers.

 

I've tested D-specs and I've tested Megan coilovers. The D-specs are were worth every penny, clear engineering and developement went into them. The Megans were horrible, no adjustment setting worked. I could not wait to pull them off the car and dumpsteer the dampers, I honestly could not resell something that horrible to another car owner. On a hunch I bought softer front springs and retested. Still not good enough to keep, but resellable at least.

Side note. I guess I went a litte too fast over a certain speed bump and snapped one of my rear sway bar mounts. I was wondering what the strange clanking noise out back was and where the slight push (understeer) came from. Leason learned.