Ziggyrama

iTrader: (15)

Hi guys,

I am in a process of selecting my replacement for my 03 shocks and springs. What I am after is a good performance setup for the street only. I do not track this car and will not track it in the future. I am not looking to lower the car much, if at all, max of 1" drop for esthetic purposes only, as a side bonus. What I want is a reasonable performance improvement. I am willing to sacrifice some ride comfort to get there. My budget is around $1400 for this.

After some searching, I am seriously considering Bilstein PSS coilovers but the rear progressive springs are holding me back. I found some references where I can put my own custom rear springs to make them liner. I believe Eibach or Hypercoil offer this option.

Some questions:

1. I believe I need 2.5" ID 7" long spring for the rear for Bilstein. Can anyone confirm that?

2. Do I have to modify the shock or the spring or is it a direct fit?

3. What rate would you recommend for the rear given the front rate of 370lbs/inch? Would I have to revalve the shocks?

As a second option, I am also considering Koni shocks and matching them with performance, minimal drop, liner springs. I think I could go up in my spring rates a bit and I could tune the dampening but I would loose height adjustability, which I may be OK with.

Any recommendations on a springs for Koni shocks?

Your help is greatly appreciated. Thanks!

davidv

iTrader: (2)

Why would you assume that a 1 inch drop will give you any handling improvement?

Ziggyrama

iTrader: (15)

I didn't...lol. I mentioned optional 1" drop to communicate that I am not after dropping the car, but to improve the handling performance on the street. In fact, I am fine with no drop at all. A subtle drop in height would be for esthetic purposes only. Sorry for not making that clear in my post.

arizzee

iTrader: (28)

I had the Koni Sports with RSR Springs on my '03 and really liked the improvement over stock's harsh bounciness. Ran this setup on the street and track without suffering driveability or control. RSRs are linear, drop .6" but are hard to find now. Yet I have a set laying around somewhere if interested...

sfearl1

iTrader: (6)

I literally just put this EXACT setup on my car this past week (Koni Sport Struts with RS-R Springs). Been talking to a few guys on here about adjusting the shocks for daily driveability while still making an improvement over stock performance. What settings were you running to combat the bounciness? All the way soft? How will that affect the handling and performance aspect? For now I'll just be dd'ing the car, but eventually will be looking to take it to the track.

sorry OP for the threadjack

Ziggyrama

iTrader: (15)

It's all good. It is relevant to the disussion. In a meantime, I will look into RSR springs.

davidv

iTrader: (2)

How many miles on your car?

Ziggyrama

iTrader: (15)

I am at 89k miles right now with stock springs and shocks. They are overdue for replacement. I have delayed the replacement due to other projects around the house...but enough is enough.

davidv

iTrader: (2)

Oh my. Yes the OEM springs and dampers are tired.

If you go with OEM replacements (say a top brand such as Bilstein** or Koni) you will notice a considerable improvement. It will ride like you remember 89,000 miles ago.

If you are looking for matched springs and dampers that will NOT rattle your teeth what about: http://cgi.ebay.com/ebaymotors/NISMO...ht_1394wt_1167

Soundslikesight

I ran koni's on my r32 vw and was quite happy with them. On my z I intended to run the same but ended up with a good deal on tokico dspecs and am equally as happy with them. Price is much better than koni's too. Currntu running them with eibach prokit and am happy with their performance for the junked roads of Los Angeles and occ. canyon runs. However if an when I track my car I intend on installing a stiffer linear spring.

Unless your dead set on height adjustment or a serious track junkie save the money you would have spent on coils and get some sway bars. The damping the dspecs provide are far more refined than I expected and they are just as nice as koni's in my opinion. Anywho good luck.

Voboy

iTrader: (58)

The OP is considering a Bilstein Coilover setup which would be a matched spring and shock combo with also the ability to adjust ride height. And it will not be overly stiff.

I would also consider KW Variant 1's coilovers. (Shocks made by Koni and are matched with springs). Either way if you were to replace the springs for linear ones you would need to have the shocks revalved.

I would suggest you buy the coilover setup that suits you. If you purchase the Bilsteins or the Koni's, ride until the dampers need to be rebuilt and then consider the linear spring/shock revalve upgrade. I don't think they'll let you down initially even with the progressive springs.

pony_killer

iTrader: (23)

+1 what the guy above said. if you want to save some more money buy some tokico d-specs and a set of springs. I personally am running the tanabe nf springs with dspecs and spc camber kit front and rear and love how my car handles now.

Ziggyrama

iTrader: (15)

Interesting. I was under impression that I could get away with a linear spring around 350lbs/inch rate without revalving. You're saying that the change like this will still require a revalve?

The more I research and think about the options, the more I come back to Bilstein PSS. I do like height adjustability if I decide to rebuild with higher rates. Bilstein name means quality and good servicibility. I also need good durability as I tend drive the Z a lot the warranty offered by Bilstein is excellent. They are not a cheap option but you got to pay to play.

I looked into KW V1 and they look comparable. I could not find spring rates easily though and some posts suggest that getting them revalved is not as easy as Bilstein. Not that I am planning to revalve but I also did not plan plenum spacer, swaybars, wheels and tires, the sound system and few other things. Something tells me I may revisit this possibility 1 year from now. Just being honest with myself when I look at the past few years.

sfearl1

iTrader: (6)

believe it or not, i got a brand new set of Koni's on clearance for $450 shipped from a nissan dealership out in Cali. found them on craigslist deals are out there man. i'll keep my eyes peeled for you in case you decide to go this route.

Ziggyrama

iTrader: (15)

UPDATE: I am adding KW V1 to my list. I found the rates in one of the sticky threads. They are progressive all around but the front rates are much more aggressive than Bilstein. It seems that all reviews say nothing but good things about these coilovers.

Ziggyrama

iTrader: (15)

UPDATE part DEUX: after much deliberation and PM exchange with Adam from Z1 I ended up going with my original choice of Bilstein PSS coilovers. As you guys suggested, I will stick with the springs as is and evaluate. If I find myself wanting an upgrade, the path is very easy. Thanks a lot for the suggestions guys. I will probably get the coilovers from Z1 sometime late next week. I'll post pics when installed which should be soon since I'll have a trusted shop do it. Normally, I'd do this myself but my kitchen home improvement project is taking up all of my spare time.

White.Knight

iTrader: (2)

I too am looking into KW V1 but i cannot find any reviews on them on
my350z.com. Im only finding reviews of the V2's. what search criteria did you use? thanks!

Ziggyrama

iTrader: (15)

I don't recall what I was searching with for V1s but it doesn't really matter. V1s and V2s are essentially the same shock where V2 offers dampening adjustability. The range of height adjustment, fit and and finish and ride quality will be the same. I believe KWs are made by Koni so you really can't go wrong with that product. KW V1 and Bilstein PSS are almost a wash when comparing them side by side. I chose Bilstein because of ease of rebuilding and I was able to find members that have info on how to replace rear progressive springs with linear ones.

UPDATE: I ordered PSS from Z1 and we had a minor inventory mix up. Z1 had a set of PSS coils in inventory but physically they could only find a set of PSS10s. So.....you know where this is going Adam hooked me up with a slamming deal and I got myself a set of PSS10s. They just came in the other day. Very excited I should probably add a set of pics to the coilovers pictures thread as I didn't see them there before.

pony_killer

iTrader: (23)

can't go wrong with the pss...good choice. are you getting a camber kit?

Gsedan35

iTrader: (10)

Revalving would only be needed if spring rate does not match damping. Going from progressive to linear in of itself does not mean a revalve would be required. One would simply use common sense and not pick a linear sprng that exceeded the peak rate of the progressive spring being replaced. Given how low the min rates are on the Bilstien and Kw coilovers, owners considering going linear, simply won't be picking rates that low.

Bilstein Pss, Pss9, Pss10
Spring rates 370/240-420 (rear progressive)

KW coilovers Variant's 1,2&3
Spring rates Front 485lbs to 525Lbs Rear: 240Lbs to 548Lbs (progressive springs)