Doggman9

I've done my research and I know the differences. Just looking for some opinions here. Which do you think will be optimal given the following

The Z is my daily driver and I race it 4-5 times a year in Autocross events. I am an enthusiast and don't mind a stiff ride, to an extent of course.

I will be checking the alignments after the install and buying what's necessary to correct it.

I will NOT get it corner balanced if I get the KW's.

Priorities in order:
1) maximum cornering performance
2) eliminating body roll
3) reducing fender gap
4) retaining a comfortable ride
5) cost

Looking at either the Swift Spec R or the Eibach Pro Kit springs to go with the Koni's.

dkmura

iTrader: (64)

Might want to rethink NOT corner weighting if you get the KWs. I use Koni 8241 Sport shocks on my street Z and like them for their durability and consistency, but adjustability- no.

On the other hand, I use the KW Spec Z suspension kit on my SCCA T3 racecar. The KWs allow much more adjustabily, but I've got to rebuild the rears after three seasons. For a DD, I'd be more confident with the Konis and either the Swift or Eibach springs.

Doggman9

Thanks for the response.

I know that I should* get it corner balanced with the KW's but I hate taking my Z to shops and letting people jank around with it. I'm leaning towards the Koni's to avoid that.

What is bad about the adjustability on the Koni's? Not enough change from max soft to max stiff?

dkmura

iTrader: (64)

Nothing is "bad" about the Koni Sports, but they are not coilovers, so corner weighting is not possible. They are also single adjustable shocks; with sufficent adjustability on the rebound side, but non-adjustable for bounce.

guitman32

iTrader: (15)

They are both rebound only, they are both twin tube designs, but the KW is probably a higher quality product overall.

I ran the Koni singles for quite a while...they are decent performer but harsher than an 03 stock spring/shock as a reference. I had to replace 2 front units because of leaks from the top adjuster (zero hassle, Koni is great).

Over the course of several autocross seasons my thoughts are hysteresis was an issue, especially given the FL heat over repeated runs. Bump was pretty good, and easy enough to dial out transitional oversteer with the rebound adjustment. I now run monotube shocks.

You are getting more with the KWs, but it sounds like you only need a spring/shock combo. The koni/spring combo is install and drive...you'll have to dial in the KWs.


I would compare spring kit rates/drops to the KW v2 specs and see if you can find comparable options.

travlee

iTrader: (8)

do springs and shocks, save the money. koni and swift springs would be my choice, followed by eibach springs

i went with the Tokico d-specs (currently unavailable) and eibach pro-kit. i like the adjustability of the d-specs and the pro-kit didn't slam me but gave a good drop with decent ride

Doggman9

Thanks for the response.
Monotube's are generally more expensive and better than twintube, right? Which monotube dampers do you run?

EDIT: Considering the Bilstein B12 Eibach Pro Kit combo now but they aren't adjustable..

guitman32

iTrader: (15)

There are a host of benefits a monotube damper provides over twin tube by design...there are a ton of resources on the web. Not that quality twin tube options arent competent in their own right. I run Bilstein PSS dampers...as you have found the comparably priced option from Bilstein sacrifices adjustability for the benefits of monotube, and is overall a higher quality than the Koni, similar to the KWs.

Where the KWs shine is their valving adjustment range is generally more consistent than Bilstein's and Koni's. I am basing this on threads from this forum over the years.


Now that we are narrowing options, I think your primary decision needs to be **DAMPING** adjustability - need or nice to have?

-If just nice, I would personally go Bilstein B12 or PSS non-adjustables (which are coilover but cheaper than both the KWv2s and PSS10) (B12 is noncoil, PSS is coilover)
-If you need adjustability, and want to stay in a comparable price range, then Koni is the one (non-coilover)
-If you want to wait and spend more, your decision becomes more difficult. KWv2 are comparably priced to Bilstein PSS10 (actually KWs are a bit more expensive - Both coilovers).


Dont forget to also consider warranty support, especially if you are buying new.

03threefiftyz

iTrader: (25)

Threaded sleeves (for the front) on koni yellows are only ~$75 for the pair. Add a set of upper mounts that accept 2.25"-2.5" springs and you are on your way. The rear spring perches are only ~$100 from Megan or BC and you can have adjustment.

/Problem solver.

guitman32

iTrader: (15)

Lol, good suggestion problem solver. By "adustability" I was referring to damping, not ride height, I edited my post above to make it more clear. From his posts is seems he definitely doesn't need ride height adjustability.

And don't forget he would need both the upper and lower adapters as well since he won't have them from another kit.

I have found that this solution isn't really worth it, as when you add up the cost of everything, you are way too close to the cost of coilover solutions. Doesn't sound like he needs to go through the hassle quite frankly.

Just fyi your car is the background on my computer

Doggman9

Thanks for taking the time to post up this information. It's very helpful.

You are right about height adjustability not really being necessary. The only reason I would want it is to get the exact fender gap that I want. I don't for-see myself getting it fine tuned by a shop to maximize performance. Maybe one day with a track car, but not with my DD right now. So, with that being said I think coilovers aren't necessary since I won't be doing them justice.

Damper adjustability.... it's close. I want to say I need it but truth is, I just want it. I would definitely take the time to adjust it every month or so to see what I like the best and maybe even adjust it before and after autocross events.

At this point, I'm set on dampers+springs but like you said, I need to decide if I want adjustability or monotube. Decisions..

Thanks again to everyone who responded.

Doggman9

Well fwiw, I ended up getting the KW V1's. Decided rebound/compression adjustability wasn't that important. I got them from NuGen Automotive for about the same price I was looking to spend on swift springs + dampers.

I'm stoked. Will be installing them on Thursday.

guitman32

iTrader: (15)

Nice work, good choice.

Doggman9

Took awhile but managed to get them installed. Went for a short test drive but turned around before I left the neighborhood because I heard some rattling/clunking from the rear. Right now the rear is at maximum drop, pretty damn low.. can't even get my fingers in between the fender and tire. Going to raise it up a decent amount tomorrow and see if I can't diagnose the rattle. From my research it looks like the shock mounting points (upper and lower) are the most likely source of the noise so I'll start there.

EDIT: Fixed the rattle. Was a pretty simple mistake we made when installing the dampers. All is good now.

ZROCM

iTrader: (6)

My objectives are different from yours such that I would like a lower ride, but with the ride quality of the 2004.5 OEM / stock suspension. My Z is a DD and I have only had it on the track twice since I have owned it 10 years. I have experimented with a number of shock and spring combinations. Most of them provided better cornering control, but they all provided a noticeable rougher ride on the city streets. I actially thought I had a good setup with a set of RSR*Ti2000 springs with the Bilstein monotube dampers. The cornering and control was awesome, but the ride on the city streets was too stiff. I returned to the stock suspension. Oh, I'm running 18 inch front and rear (275/40 in the rear and 245/40 in the front).

I have adjustable upper control arms and in the rear the SPC oe bolt and and SPL lower arm.

So, I'm wondering how you like the KW V1s?
How's the ride quality when compared to stock?
What do you think about the quality of the KW V1s?
Are you missing adjustability by not purchasing the V2s and V3s?

Thanks in advance for any comments that you can provide.
Best regards,
ZROCM

Doggman9

I posted in my other review thread too but I'll answer these questions here too.
https://my350z.com/forum/brakes-and-...r-results.html

1) I am extremely happy with the KW V1's.

2) They are definitely stiffer but I would not consider them harsh. They soak up the bumps very well IMO. The OEM suspension moved around more than the KW's which are planted and controlled. Cornering feels much better with the KW's and I no longer get wheel hop during a burnout.

**Disclaimer: I wanted a stiffer ride. The OEM suspension felt sloppy at 90+ MPH and it rolled too much in the turns for me so my review of the KW's might be slightly skewed. Like I said, they are definitely stiffer. However, I would say with confidence that they soak up the bumps very well and provide a comfortable ride. My girl agrees whatever that's worth.

3) Quality is top notch. Everything fit perfectly and felt the opposite of cheap. The only thing I can even complain about was the paint on the rear springs. There was some chips/scratches in a few spots but I imagine that was from testing at the manufacturer. It didn't bother me at all.

4) When I first started looking into replacing my suspension, adjustability was a necessity. In retrospect, that was stupid. The way I see it, if you are not racing your Z and adjusting the suspension from race to race, adjustability is simply not necessary. Racing experience and in depth suspension understanding are prerequisites for properly adjusting a suspension. Unless you have that experience or want to let a professional shop adjust it for you then the V1's (preset by KW's engineers for optimal street/track performance) are the way to go.

ZROCM

iTrader: (6)

Thanks for the comments. It all sounds great. It's good to read that the KW V1s soak up the bumps and no wheel hop experienced. Yes, I also thought at high speeds the OEM suspension seemed somewhat loose. Based on your comments looks like I will be considering this setup. I was also looking for a 1 inch drop, but any further as I understand will decrease the handling.

Thanks!
ZROCM