I'm not only a newbie to modding but I'll readily admit that I probably know less about the suspension from an academic/scientific standpoint than any other part of the car but I know what I like to feel when I drive. At 36, I'm also one of the older guys on the forum, so I have an unusual desire (based on what everyone else seems to want), which I am unsure how to best achieve.

FYI, when I get rims, I'm planning to go wider; not bigger (I'll stay w/18"), so as not to sacrifice ride softness. FYI #2, my build date is 3/'04, so I have the new shocks which eliminated the "bouncing" problem.

My desire is to make the car feel more stable in the corners and improve adhesion at the limit (apart, of course, from the necessity of buying great tires) w/o having a harsher, stiffer ride in general, esp. while tooling in a straight line down the highway, since my car is a daily driver. I can live w/the ride quality as is, but I don't want to give up much more comfort, and I don't plan to track the car. And I do know that, of course, trade-offs are involved by necessity.

So: Would sways alone be my answer? Do sways negatively affect tire wear in any way in general (have seen only some isolated complaints about particular products)? Would any aftermarket shocks in combo w/the sways help the ride w/o sacrificing cornering ability? Any other bright ideas I might be too ignorant to have even considered?

All advice appreciated, especially from the mechanical engineer types, or those who wanted what I do, but found a solution. Yes, I read the faqs and did a search; I don't claim to be a perfect "searcher," but it seems like everyone modding the suspension was wanting to track the car, lower it and/or go stiffer.

 

if you want a more street suspension (coilovers), look at the hks hypermax ls(+), tien type cs, cusco zero-1, tanabe sustec pro s-oc(II). these are all coilovers that will improve handling and are designed with daily driving ride comfort in mind. they all have height adjustment and some of them have dampening adjustments as well.

one of these suspensions with a set of sways would probably all that you need.

 

Sways are your answer.

 

I know you don't want to go into tires, but they are by far your best bet for increasing overall traction . You should always start with tires. They are, afterall, the only thing that connects to the ground--everything else just controls the tires.

That being said, shocks may be a good fit for you, coupled with some springs if you want. Sways are mainly for adjusting the balance of the car (i.e. reduce understeer), but they also reduce roll which helps. Coil-overs will probably be too stiff for you (except maybe something like the Tein CS, but I am not convinced of their performance value yet).

As always, ride feel v. traction usually are opposites--you usually have to give up one for the other.

 

I would start with a set of sways first and see how you like it. Stiffer sway bars will make your suspension feel stiffer on the road--imagine hitting a bump with one tire: spring compresses and sway bar twists, both resisting the movement of the wheel. I put stiff sway bars on a ProSolo car and actually had to install softer coilover springs because the sways made it too stiff.

If you do install aftermarket springs or coilovers, make sure to get progressively wound springs--they will perform like a comfy soft spring when they first compress and will get firmer as they compress more (fighting body roll and improving handling). I'd prefer to get coil overs and either use progressive springs or tender springs (an additional spring on top that keeps the stiff spring in place at full droop and also softens the ride over small bumps). At least with coilovers it's easier to buy springs and swap them in until you get the ride you want.

 

Thanks for the info, all. A couple of the posts reminded me of why I got Cs in chem. & physics classes in undergrad. So: Which sways are stiffer v. less stiff? Eibach? Nismo? Stillen? Other?

And which coilovers and aftermarket springs are progressive rate as opposed to linear rate? After all, they don't usually tell you this stuff in marketing them, i.e., "they'll lower the car .8"; "they'll help you run faster lap times at the track"; "they're from the leader in aftermarket spring technology for the last 25 years"; and generally, "they're way cool".

 

Mmmmh, that's a difficult request you have !

Not being a 350Z owner, I can't give specific advises. The chassis dynamics change from model to models.

But for sure, an easiest way of reducing body-roll and weight transfer in a curve is to stiffen the sway-bars. Both front and rear, keeping a simillar ratio between them to keep the current over-steer under-steer behavior of the car.

These do have a draw back tough. Stiff sway-bars tend to have both wheels on an axel moving togheter. So a bump on the left wheel that pushes the wheel up will also tned to move de right wheel up. So on really bad surface (lots of potholes, gravel, snow) you will end up with less traction because wheels have troubles maintaning contact to the ground. Confort will also suffer because the chassis gets thrown around a bit more in these situations.

None the less, the benefit of stiffer sway-bar will excide this drawback in most situations.

Progressive would certainly help with confort. But I'm not sure you would gain in cornering. The car would take more roll for a give curve. Hurting weight transfer and suspension geometry.

Bigger shocks will also help maintaining latteral stiffnes, but I don't know the availlability of these for the 350Z.

Lots of otpions are available. But your "comfort" request bars them out (stiffer springs, lower car, improved dampers..)

My 2 cents.


Sorry for the spelling... French Canadian writting...

 

Darthvol, mechanical engineer here. I have both a 240 and 350, with occasional tracking, but more priority on being a good daily driver. Rampant has the best advice for you if you say "no tracking and daily driver": start with TIRES first! Go to a wider rim and get grippier tires. Drive. Evaluate if that is what you want or what do you want more (and are willing to give up to get it). Sways do have an effect at the limit, but will negatively impact daily driver comfort. Springs will lower the car and impact ability to avoid chuckholes and road debris - not to mention speed bumps! Only you can decide what your daily driving road is like and what compromises are acceptable. (I for one refuse to lower my car one sixteenth of an inch because of scraping my front spoiler now at stock height if not careful over the street to driveway transition at home!) You have to decide. make one (mod) step at a time. Drive. Evaluate. Mod, or Stop & enjoy the ride! HTH