Sebastian777

Hello all,
So I bought my 05 350z 35th Anniversary last week. The car will be mainly used as a commuter for about 80 miles per day through country back roads. The roads are hilly, uneven, and rough in some places.

I'm looking to set my car up to be more sure footed in these conditions. I just put Pirelli Pzero All Season Plus tires on the car. I don't plan on tracking the car. I do want something that is "forgiving" and easy to recover when pushed a little too hard rather than something that just loses it.

So what should I start out with on the suspension? On other cars I started out with sway bars, but am not sure if that's the best place to start with a 350z.

MicVelo

Since you've already done the FIRST STEP with tires, next go with an alignment UNLESS you're ready to do the hardware, below. (And with any/all, you're going to want to align after each step.)

In this order if you're building gradually (on a budget as it were):

1. Adjustable sway bars (tuned to your style/abilities) - Eibach, Hotckis

Then if/when you "outgrow" the bars and want more (bars alone may be sufficient depending on how worn the rest of your suspension is), next...

2. Shocks - Tokico Blues (~$400/set) on the lower end, Bilstein or Koni on the higher end ($800-1000/set). You don't need coilovers for street use but if you opt for them, might as well go with full coilover F&R, eliminate rear spring bucket and add in toe arms. But IMO, overkill and ride goes to hades.

3. Springs/Alignment Adjusters - advise you do springs with shocks (if you plan to do springs at all) to minimize your time or labor charges. You don't need super stiff/low springs for commuter/fun. 3/4" drop and you may not need alignment adjusters (but good idea to have alignment checked then get them (front UCA, rear camber arms/camber offset bolt) AS NEEDED.

It should be noted that the '05 already has the "updated" spring/shocks (over the '03-04.5) and you may just want to do shocks and stock springs (NOT the other way around though... not lowering springs on stock shocks - ride will suffer horribly with little/no improvement in handling).

Doubt you'll need much more.

JMII

VDC is your friend... leave it ON. Don't be a hero, too many Z's in ditches because people think they can drive better then a computer.

dkmura

iTrader: (64)

Mic has already posted his usual and thorough advice, and summed up what your options are. I might add that you'd be wise to do some additional values clarification of what you want from a handling update before purchasing any new parts. Nissan engineered the Z33 to understeer as you approach cornering limits, and for the vast majority of drivers, this might be the safest approach. If you want something that is "forgiving" and "easy to recover from", it can be argued the OEM suspension is a good option. Even adding stiffer swaybars might not help on rough and uneven country roads, particularly if the pavement is wet or slippery.

If I were you, I'd take more time to really get to know your Z before you change anything. Listen to what your backside is telling you on your daily commute over the next few months, and if you decide more lateral stiffness or better dampening is what you seek, you'll have a much better idea of what to do.

Sebastian777

Thanks for all of the advice.

JMII, I don't plan on turning VDC off anytime soon.

Mic, thanks for all of the advice, that is what I was looking for. I got my tires done at Tire Discounters, so they are aligned, to factory spec I'm assuming.

dkmura, you are right, I probably should get to know the car better. The last fast car I had was a Stage 1 Subaru Legacy GT. I'm used to the ultra planted feel AWD provides. I haven't got too crazy with the 350Z yet, but it feels like it wants to oversteer, though I haven't broke traction on a turn yet so that might just be in my head.

One thing I have noticed that I don't care for is going over breaks in the road at speeds of around 40-50 or higher. Even if I'm just in cruise control, I feel the back end wiggle, shimmy, what ever you want to call it. New tires seemed to maybe have helped, but certainly didn't eliminate it. Drastically different car, but my Crown Victoria never did this over the same breaks at the same speed. Is this something that is just part of a 350 and I should get used to it, or is there something I can do that will likely correct it?

dkmura

iTrader: (64)

The static weight distribution of your Z is close to 50/50 and slight RWD oversteer over broken pavement is no surprise. If it really bothers you, take it off cruise control and just learn to use quick hands to correct. The Z really needs to be driven and is certainly different from any Subie or Crown Vic.

MicVelo

How many miles on the car - and, I presume, the stock shocks?

I alluded to the original '03-04.5 spring/shock combination Nissan used. It was pure cr*p. Too much bounce/jarring ride particularly over irregular surfaces like you mention.

It's highly possible that your later model is riding as such and has worn shocks; and is pretty much riding over irregularities on spring action alone with little or no damping from the shocks.

Being that the car is used as as commute vehicle and ride comfort IS a necessity, I'll amend my initial shock recommendation with "Go Bilstein".
They have the best control with civilized ride of any shock available for the Z. Koni Sports (Yellows), even on softest settings, are livable but you'll "feel them". Not horrible but not nearly as comfortable as Bilstein.

If these road irregularities you describe with associated skitter across them is your primary concern, do the shocks first then. Bars can be added after the fact. Remove that issue THEN see where you need to go from there.

And your police car Crown Vic (laff!) is about as "orange" to the Z's "apple". Hahahahahaha!

Sebastian777

dkmura, it happens whether I'm under acceleration or cruise control. It's not bad enough that I have to correct it, it just give an uneasy feeling that I worry about when I drive it in wet conditions.

Thanks again MIC
The car has 63k miles on it. I haven't seen any apparent aftermarket parts on the car, so it wouldn't surprise me that the stock shocks are still on it. I have a feeling this car was really taken care of in the beginning and then left alone. The front tires were dry rotted and had 2008 dates on them. The passenger rear tire had almost no tread on the inside and the driver rear was a cheap milestar tire.

While I don't want to feel like I'm driving a purpose built track car, ride comfort isn't THAT important to me. I don't mind feeling the road, I just don't want something so stiff that I lose performance (or is unsafe) on the less than stellar roads that I commute on, especially in the rain.

Is there a specific model of Bilsteins I should be looking at or should I dig in and research it? Also, are adjustable shocks (such as Koni) easy to PROPERLY setup by a novice, or should I go with non adjustable and keep it simple.

nizmo_0385

iTrader: (5)

nismo struts! happens to be some for sale in the classifieds too!

MicVelo

Well, there are two models of the Bilsteins (not including their PSS "coilover" kits) for street/occasional track Zs. The B6 - known as "Heavy Duty" (HD) or B8 (Sport), which are specifically made for use in lowering applications - although both can be used with sport springs. (I had B6 and they're great but the B8 slightly shorter body might be a bit more "accurate" in use....splitting hairs though.)

They (Bilstein) make/package something called the B12 ProKit which originally came with B6 HD shocks with Eibach ProKit springs affording a 15mm drop. Current B12 ProKit appear to be packaged with B8 shocks according to more recent users/buyers.

I can attest to the effectiveness (and comfort) of this kit, I originally ran it with the Bilsteins; but when my kid needed shocks for his Z, I gave him my 'Steins and swapped out for Koni just for experimentation's sake. Happy with either but edge to Bilstein.

I should also note that when buying the ProKit spring/shock setup, it's usually cheaper buying the package than buying springs and shocks separately. Check around with this site's sponsor vendors.

On adjustability, it's not that big of a deal to adjust them but for the access to the rear adjuster at the top. But the reality of it is unless you're adjusting for varied track conditions or you're a wheel ho like me and I tinker with the adjustment to suit the weight and type of wheel/tire setups I'm running, it's pretty much a "not required" scenario. Honestly, if I were doing it again, I'd get Bilstein again. Install and forget.

Oh, gee, I wonder who might be selling those, y'ho! Hahahahahahaha!

But nizmo_0385 isn't wrong. Nismo struts are awesome. My bone stock Niz was/is the "best handling car I've owned out-of-the-box" and the only thing differentiating it from a non-Nismo Z was the shocks/springs.

Sebastian777

One thing I have to take into consideration with the suspension, is that due to rough pavement, steep driveways, and gravel roads, I have to be careful about lowering my car.

It looks like I can get the Bilstein ProKit for about the same price as just the shocks ($850 ish). How big of a difference will the springs make in handling in the conditions I have described versus the stock springs with 63k on them?

When you said the Bilstein Prokit lowers by 15mm, is that right or is that typo? The specs I'm seeing is around 30mm on average, of course real world doesn't always agree with specs.

dkmura

iTrader: (64)

I might be able to help with the Eibach Prokit springs question. It's a progressive spring that has lowered my Z about an inch. I like the look and supple feel of this spring set with my Koni 8241 dampers. After almost 12 years of use, they remain very responsive, but there's no doubt they make steep driveways and speed bumps a no-no. Depending on how rough the pavement is, that could also be a concern.

Bottom line: keep the OEM springs for increased ground clearance, but replace the shocks.

MicVelo

Can't say I've seen a -30mm spec on these because for sure I would NOT have bought them. Like you say, I like to drive where there are driveways and such. Perhaps you were looking at specs for Eibach Sportline which is 1.2" or 30mm.

The original specs for ProKit were something like 3/4". And that's what I'm seeing CURRENTLY.... -19mm with Koni Yellows. With the Bilsteins, the car sat at -15mm due to the tendency for the Bilstein's high pressure design to raise the car back up a few mm's versus the 8241 Sports low pressure TT design.

BTW, these are measured (settled chassis) heights from smooth, level surface to fender lip directly above the centerline of the hub.

This is -19mm and I clear just about everything.



Perfect for where/how I drive; by design. (So long as you don't include the Porsche muffler I ran over - direct hit - the other day on the freeway. Still, no damage, body or undercarriage)

dkmura

iTrader: (64)

Impressive- you had time to note it was a Porsche muffler before you hit it!?

Ah well, any Porsche you pass is good in my book!

MicVelo

Well, I do have keen eyes for parts.

Nahhhh, was tooling along a number of car lengths behind an SUV and he then made a casual move to next lane - no evasion, just a lane change. Soon as he did it, this object on the road (a muffler assembly with pipe laying crosswise in the middle of the lane) appeared and I looked around quick, fehhh... no exit, braced for impact, BAM! KLANG!!

Kept eye on mirror and gauges to see if I'd dropped oil pressure or emitting anything smoke/liquid wise behind me. Nada.

As I moved over to get off the freeway, I noted a Porsche off to side of road and guy was looking under his car. I didn't see tailpipe so guessed it was his. In reality, it might have just been someone else's and he ran over it too and was on the freeway checking out his car.... dunno.

Any event, I got off and inspected my car. Didn't seem worse for wear other than a couple scrapes on lower part of front fascia (but it's whacked already so no can tell diff). This week when I had car up on stands, I checked again. Nothing I could see was different so all good.

Z33_Drvr

FYI. I just did a spring and damper replacement myself about a month ago. Bilstein B6 dampers, Swift Spec-R springs, also did SPC rear camber arms and Whiteline rear subframe bushings while I was in there. I plan on getting Z1 Adjustable FUCA pretty soon. Mine is a 2007 with 55K, but I noticed exactly what you (OP) described. There was a minor difference in oscillation response for front vs rear. It led to a weird feeling in the seat lol. Keep in mind at the time I already had Hotchkis sways installed. So I wasn't completely stock. But I still experienced the same "wiggle" as you put it. I am in Tucson and the roads here are horrible... Everything is blacktop and they just keep patching things instead of repaving. I came from Texas and can relate to the uneven roads you describe. But what I am getting at is things are worse here in AZ and I am still happy with my lowered car. I have a Very similar setup to what you are looking into, and I am very particular (one) with the parts I spend my money on and (two) with ride quality since this is my DD as well.

As far as ride height and ride quality. I am very happy! Majority of the time it feels stock (normal, straightline driving), except when you hit an abrupt bump in the road it feels a little stiffer (roughly 10% over stock) not a lot but enough to notice a difference. Then again I have the poly rear subframe bushings as well... so.. theres that. But this is where I think the B8 dampers would be a better choice. Now the real difference comes when I take a turn. Body roll (which stock didn't have a lot) is virtually eliminated! The Eibach's may vary a little since your numbers are a little different. But they are pretty close to what I have now.

If I were you I would opt for the B8 dampers. I have the B6's and overall they will probably be fine in terms of service life, but I do notice that they are a little overdamped with these springs. If had it to do over I would get the B8's but several ppl told me the B6 would work fine and they do don't get me wrong, but I think the B8's would be a better match. You got a little more info than what you asked for, but just sharing my experience for what its worth.

Sebastian777

So after reading a lot and putting thought into it, I'm not really wanting to go with lowering springs. My research has shown that any performance gain I would get, isn't really worth the hassle and costs associated with driving and installing them, for me at least.

Are there any good springs that DON'T lower the car and make a noticeable difference versus the stock springs?

Also, if I'm not lowering the car, is there any reason to go with Bilstein B8s vs B6 HDs?

MicVelo

Yes and No.

If you really want to swap springs for performance but without lowering, I would recommend you try to locate a set of OEM Nismo springs. They do NOT lower the car (maybe a few mm if at all) but the spring rate is "enhanced" for performance.

Elsewise, stick with the stock springs. Nothing wrong with pairing those with a good set of shocks.

And no, there's no reason to go with B8's as they are a derivative of the B6. Only difference is the B8 is designed to be used with lowering springs. They are valved exactly the same... NOW.

Previously, the "HD" nomenclature of the B6 meant they were designed with OEM ride height in mind and the "Sport" name in the B8 simply meant they were for lowering springs. They have since re-branded them "B6 Performance" and "B8 Performance Plus" but they are the same product family (technology).

EDIT: You also said, "...any performance gain I would get, isn't really worth the hassle and costs associated with driving and installing them".

Welllllll, keep in mind that you DO have to remove/disassemble the entire shock/spring set up front so no labor savings there. Rears are fine though, just plug n' play.

Z33_Drvr

So if they are valved exactly the same now? Then what's the change in design, and how are they made differently for lowering springs? Where are you getting this information?

MicVelo

The shock body of the B8 is physically shorter and the by-product, a shorter stroke.

http://www.bilsteinus.com/

From that site:

What difference is there between BILSTEIN B6 Sport and BILSTEIN B8 Sprint shock absorbers? (Note that this FAQ question is a couple years old so the nomenclature is the original text.)

The BILSTEIN B6 Sport is a mono-tube gas pressure shock absorber designed to dampen wide-ranging vibrations very precisely. Where an oil shock absorber produces an oily foam and creates a spongy driving feeling after a very short distance, the BILSTEIN B6 Sport remains constant, precise and stable. The BILSTEIN B8 Sprint is a mono-tube gas pressure shock absorber specifically designed to be used with lowered vehicles with shorter stroke. It also offers the same advantages as the BILSTEIN B6 Sport shock absorber.

===========

While looking into B6 Damptronics for my non-Z car, I came across an article (I think on the Bilstein site or other credible ref point; NOT someone just speculating on a forum) that references the "B6/B8 product family" and a distinct comment about the B8 being an offshoot of the B6 with common TYPE valving to provide like dampening throughout the range of movement. (That was news to me.)

Physically, it's NOT necessarily using the exact same physical orifice/valve sizes, rather, valved accordingly to provide identical jounce/rebound characteristics. Makes sense, given the shorter physical length of the body and presumably, the shaft stroke. So guess my original wording was about as clear as mud.

Let me clarify: they may or may not be valved identically from a physical standpoint BUT jounce/rebound characteristics (results) are the same; just one being shorter so the springs don't fall out. Laff. (There was also some mention of tuning them - B6 and B8 - similarly using a shock dyno but the rest of that escapes me at the moment.)

Gotta find that wherever it was. Will post if/when I find that again.