Stock suspension done at 20k
 

I don't have a lot of miles on my car, but is it possible for the suspension to be worn out at 20 to 25k miles. I just seen to have a tough time running with people I normally am able to. Any suggestions on good cool overs? Thx

I don't know but I guess anything is possible if you squint your eyes and wish really hard.

While they're not coilovers, I'd recommend Koni Yellows if you already have aftermarket springs. You can adjust the dampening by a good range to suit your needs. I love them.

Do you have springs?
If so, yes, it is possible, otherwise, it could be sag

dAvenue,

I was look7ng at the Koni's today teying to see where the adjusters are located. I couldn't really see from the pics I saw. On the rwars it looks like you depress a detent then twist the shock body xloxkwise of counter CW for more or less.

do the front work the same way or is the adjuster at the top of the strut rower. I was looking at these with the swift springs for aurocross and some trak HDPE eventa.

Thanks

Kinda vague on the description. Maybe post some times, what feels different, etc. 20K seems pretty early, but if you have been tracking/AX very hard for 20K then it's possible. Figure one mile at a track is equal to like ~ 7 miles on the road or something like that. You would expect a suspension under normal DD to only last around 50-60K or so.

Sounds like an excuse to buy an upgrade ;).

The fronts are adjusted on top of the strut tower; easy access. The rears have to be removed; the dampening is set with a pin that rotates the slotted adjuster.

Koni North America - ITT

My car is completely stock. I actually noticed the problem last year at the track, but I just thought it was the decline of my driving skills and being older that were causing myself to slow down. While I still believe that to be true, I do find it weird the car is leaning all over the place. Someone who was following me had shots of my car leaning all over the place in the turns, my car just had uncontrollable sway. In the car, I had no confidence whatsoever when driving. Unfortunately I never had a chance to run against other stock cars as everyone I saw was modded. I ended up being about 3 seconds behind a Mustang 5.0 with coilovers and exhaust, 4.5 sec behind a 997.2 GT3 and 4 sec behind a Camaro SS with coilovers and exhaust in a 3 miles track. To make it worse, the stupid car started to slow down later in the day for whatever reason too. I think I took some bad advice and drove a different line, I ended up losing a second on that.

I also believe the grip provided by the RS3 is really magnifying the issue too.

Oh yeah, the freaking diff was starting to act up too. I think it became an open diff in the later sessions, causing massive inner wheel spins.

No logs yet, too tired to do anything now

20k to 25k certainly isn't early for a car that sees substantial aggressive use. That sounds like a normal life span for a damper if you ask me given the circumstances. Normal street drivers will see 50k to 75k life spans for their suspension, but for us it's really not uncommon at all to see them worn down early like that. And you hit the nail on the head with the RS3 tires amplifying the issue. It's simple, add a ton more grip and subject the suspension to extremely intense suspension forces for extended periods of time and you'll have a shorter suspension life span. Same thing goes for tires. I rip through tires on every sports car I have owned in anywhere from 8k to 15k with mixed HPDE, street and autocross use. Time for you to rebuild or replace your dampers man.

^^^ or buy Nismo dampeners from me!

The Nismo dampers aren't stiff enough for what I want to do. I am looking for KW V3s, unless you guys have other suggestions. I just want to make sure it is a suspension problem before I go ahead and spend $2K on it.

So here is a different angle I am looking at. I had the G plots overlaid with the tracks I did in the past. I understand tracks can have different effect on how hard you can go around the corner, but all I try to look for is trends. If you look at the charts below, you could see I was pulling more G in the track days when my car was newer. I don't know if it is related to the new RS3 I got, but I doubt it as they should be faster than the RE11s.

http://imageshack.us/a/img32/7294/26dl.jpg

http://imageshack.us/a/img198/4761/few6.jpg

http://imageshack.us/a/img571/5394/ni0f.jpg

Robi Spec'd KW Variant 3 Clubsport vs BC Racing ER Type Coilovers from RA.

Swift springs either way.

track use and higher grip tires, plus all the DD miles. for sure you can wear out the stock dampers in that time frame.

KW V3s when set at the correct height, trimmed down rear bump stop and remove front black bump stop (not the yellow one) and correct damper settings are super comfortable and handle great. I recommend a larger front sway bar to compliment your wide front tires though

I've never really been a huge fan of suspensions manufactured in Asia because they tend to go overly aggressive on valving their dampers, but I guess the best answer depends on where you're going with your car. Always very highly sprung and may be a better choice for a Time Attack car. Friends of mine that work on Grand-AM cars say they run JRZ or Ohlins setups typically, which are obviously crazy expensive but amazing suspensions, but then run Bilstein for endurance racing because of the durability of the dampers. I am pretty sure they make PSS10's for the 370Z although they don't seem widely popular. I've always loved Bilstein setups I have had or ridden in. KWs are never a bad choice on any platform. I had BC coilovers in the past on another car and they were really harsh and the entire suspension corroded and locked up so badly that the coilovers were nearly garbage afterwards. Another friend of mine had 3 out of 4 dampers fail within 5k miles on the suspension. Just my $.02

Are they good to buy used?

I don't know if pss 10 is available. If so, I want to get a used set and have custom specs put in

Depends on the suspension, but typically that's one component I would prefer to buy new. People will say all "highway miles" or only 5k on the suspension and you have no idea really... I guess use your judgement on what looks to be in good shape. I would like the satisfaction and comfort of brand new dampers covered by a warranty of some type.

I think I saw the PSS10 on ZSpeed, but not too sure. Back in my BMW days Ground Control let you essentially build your own setup from scratch. Custom spring rates, spring lengths, dampers custom valved etc. It was sweet if you wanted to do your own thing and knew how to setup a car. I had a nasty suspension setup for my STi with custom double adjustable Koni dampers with independent rebound and bump adjustment. Too bad they don't have any offerings for the 370Z.

I tend to like European designed dampers. The critical dampening rates tend to be much lower so it's a lot more compliant over bumps which makes things a lot easier on the car for longer term durability and comfort. Softer doesn't necessarily mean slower... Gone are the days of super stiff, bone shattering suspension for quick times. I haven't explored a whole lot myself for the 370Z because I just got one and I like the car stock right now, but I would explore Bilstein, Koni, KW and other offerings before going straight to like BC, Cusco etc.

There's two or three 370Zs that race in the Continental series or whichever the series is. They're at Lime Rock Park this weekend. I think one of the guys on the team is on this board, but I would consult their experience to see what setups they've been running for the best real world advice. When I choose suspension I consider price, durability, warranty, dampers/springs offered.