Skrill

Hmmm ... does the actual setup relocate the rear spring to the shock body??

EnthuZ

iTrader: (2)

NO!

I thought I mentioned that the delay in their release was due to the adjustable rear spring seats being made....

The catalog pic is just a generic shot.

I haven't asked about the Phase I or II.

As for pricing......think the higher of the 2 mentioned as being closest.

I'm off to the track, so I doubt I'll be able to add more news till Tuesday, but keep the questions coming.

Here is an old shot from last August, but I'll bet it's accurate. (NOT the 4 way adjustable black one)

FritzMan

Their selected spring rate bias is very similar to what I'm now running with my JIC FLT setup. Instead of the standard kit of 10kg front and 12 kg rear (560/672 lbs), I'm running 10 kg up front and 9 kg rear (560/502).

The softer rear provides a lot more corner exit traction while the stiffer front allows agressive turn-in and sharper steering response. Not only has handling improved, but I found that a softer rear really improves the street ride. It seems as though the rear is more sensitive to spring rates than the front.

Gsedan35

iTrader: (10)

Thank you for your comments. So you ran the original 560/672 setup first, then you switched to the 502lbs setup and your impression's are drawn on having tracked both setups?

Gsedan35

iTrader: (10)

No you didn't mention the reason for the delay that I ever saw, thanks for clearing that up.

FritzMan

I ran the 560/672 all last season in Solo2 and felt the rear was too snappy. It was good for rotation but bad for weight transfer/traction when exiting corners. Also, any kind of bump would upset the tire's traction because the rear was just too stiff.

Throughout the '04 season I played with sway bar rates and the JIC's adjustable compression and noticed that a softer rear allowed more traction without ill effects to handling. The car certainly felt different, but the clock (and butt) said it was a good move.

This season I'm setting up the car for Solo1 so an even softer rear is ideal (some understeer). Initial testing with the current setup has been quite favorable.

Note that I'm running 245/40/18 Kumho MXs front AND rear so understeer has been substantially tamed with that setup alone.

Gsedan35

iTrader: (10)

Thank you again for your imput, your comment's are appreciated beyond measure. I especially appreciated where your comming from for several reason's. One your not tainted by a product line or having to only talk in a way to support what you sell and your doing the type of event's I'm more inclined to benefit from since I will never see high speed road course's. Furthermore I've been in need of imput on trial and effor testing before I can relax from the position of being against high transfer's of spring stiffness to the front. Your imput helps a great deal in that regard.

daveh

iTrader: (9)

Gsedan35 what are your motives in your efforts in trying to be as close to the stock roll stiffness as possible? What are your ulitmate goals for your car? You have done an excellent job in your data collection and analysis and have posted much information along to the community here so thanks for that.

palepony

iTrader: (8)

+1 thanks to gsedan

your posts have always been most informative

also to fritzman

pp

Gsedan35

iTrader: (10)

Both of you are welcome and thank you, this community works best when we're all willing to help or at least talk things out.

Well we know what tuning law's tell us as far as spring rate tuning to alter roll stiffness balance. But, we've never had anyone come forward until just now that has tried both on this platform, a rollstiffness transfer to the rear, then to the front. Now we have and thankfully both theories were used by the same person and the same car and from someone that does have a product to push or a storefront to sell from to possibly taint his answers. Plus over time, I've heard faint whispers about the soft oem suspension allowing geometry changes that play against the platforms suspension dynamics/at the limit behavior (toe changes in the rear is what I've heard the most of) All that being said, I've alway's held that whatever "starting" setup I go with, I'd be willing to alter spring rate balance from that point in order to get the car dialed in. Now, I'm not so adverse as before to allowing higher front wheel rate increases then I was before.

Ultimate goal for the car. Having a setup that would perform very well in solo2 without ever actually entering a event. Yes, I want that certain performance level and I'm thinking that about a 50% increase in spring rate is about right, any higher will go too far on the street for me. Thing is, my better half hasn't let me do near the things I've wanted to do on this whole path,...or I'd have plenty of findings to share myself.

daveh

iTrader: (9)

I spoke with unitech racing and they said it would be ok if I published their pricing. The introductory price for the first 20 kits will be $2995. This includes all hardware including springs, shocks and rear perches. If you want spherical bearing upper mounts you will have to add $325 (I don't know if this is per pair or for all 4).

gsedan35 his response to your roll stiffness questions was that they use books like Race Car Vehicle Dynamics (I think is the one he mentioned) to set up their all their race cars and there are many variables to keep in mind. This is my oversimplified watered down version since I know nothing compared to them

Just passing along info. Deciding if I want to spend the $$ is my next question...

Dave

azrael

Do you know why these numbers are a lot higher than what's quoted in their catalog, as well as the prices for other vehicles?

Their catalog mentions $2300 for the Phase 3, and $2600 for the Phase 4 on the 350Z. Other cars (S2000, etc) are listed at even less than that.

daveh

iTrader: (9)

The pricing in the catalog is only for the shock itself. The shock is technically a stage 4 because it is shortened and has race valving thus it is $2600. The $2995 cost from unitech adds their springs perches and hardware (minus the upper mouts)

EnthuZ

iTrader: (2)

I don't post for a day and a LOT of information is shared. Maybe I should just shut the F up!

Ran a HPDE at Blackhawk Farms on Kumho MX's in damp conditions today, and, I'm totally fed up with their track performance. Dry, almost OK, but wet.......

I'm surprised that FritzMan has had good luck with them.

I can't wait to get the RT-615's on.

Back on topic. It sure sounds like this new package will work wonders for MANY different driving conditions.

As to the price increase over what is in their catalog.......I don't think they anticipated the cost of the separate rear spring seat height adjuster.

FritzMan

Gsedan35, glad to hear you're interested in details behind the 350z suspension - people around here look at me strange when I babble excitedly about my findings. I've spent quite a bit of time documenting my changes and their results. I just corner balanced the car last week for the first time (a lot of final spring rate variance!) so I've got re-examine all of my settings to see what still applies.

Back on topic, last year on the AutoX/Track forum there was a thread discussing the viability of a BS legal front sway bar upgrade. Although a stiffer spring rate up front should promote more understeer, it is thought the camber limitation of our setup (especially at stock ride height) actually benefits from a stiffer front resulting in more bite. Personally, I find the front can only handle so much sway stiffness before steering feedback/feel deteriorates. Hence, I decided to play with spring rates to achieve a similar effect while preventing the negatives of an excessively stiff front sway.

While a lot of this could also come down to driving preferences and techniques, there are some manufacturers of coilovers who felt the same way and spec'd a stiffer front rather than rear. It's good to see the Truechoice package going that way as well (meaning I might actually have some minimal skill setting up a car) .

Keep in mind that due to the design of our rear geometry, the actual spring rate is substantially reduced through a leverage effect compared to the front. While I am running a 10 kg front and 9 kg rear, the actual spring rate at the wheel has a much larger variance than 1 kg. I wouldn't be surprised the OEM setup has almost identical effective springs rates at the wheel despite the apparent rear bias.

EnthuZ, I agree the MXs have some disadvantages, but they're (really) cheap, pretty much as sticky as any other non R compound tire, and don't grease up under heat like the Azenis 215. The MXs have been good enough to FTD me several events against many other R compound rides. Having said that, like you I'm looking forward to slapping on a set of 255/40/18 RT-615 later this fall once my MXs burn off.

Skrill

I could NOT disagree with you more ... Kuhmo MXs rock.

I have run them for 11 track days and 6500 miles. The work very good at temp and proper pressure (40-43 psi) and grip extremely well. At my one damp track event they were as good as any tire I have run (that is to say -- f'ing scary as hell, but what to you expect, the track is wet).

I have outdriven many R-compound shod cars at the track -- including some GT3's with Pilot Sport Cups (granted -- the driver had to suck to be that bad). But I out lap many R-comp cars.

If you are going to run a street tire at the track -- I think MXs cannot be beaten.

Now -- back on topic -- can't wait to get the Unitech suspension.

350ed

iTrader: (17)

Am I the only one shocked by the pricing?
I was expecting half that. Konis run <$700 and springs are $200ish. Perches seem to add $300 that we weren't considering initially. Then revalving and adding another adjustment for the konis is very expensive I guess.
I'm just annoyed since I was hoping to switch to this and won't be now...

daveh

iTrader: (9)

I agree, is as anyone getting these for sure? I'm still on the fence.

palepony

iTrader: (8)

i thought i was going to be on the "for sure list" but $3K is making me think twice; was expecting $2000-2500

i may wait to see the phase two offering

pp

dklau33

iTrader: (17)

$3K is pretty steep but if they are superior to other offerings out there that use really high spring rates (Tein Flex, JIC FLT-A2, etc.), then maybe they are worth it.

Fritzman:

Your assesment and experimentation with your JIC setup is really interesting. I know this is a subjective topic but how is the street ride to you with your 10kg/9kg setup? Okay for you as an everyday driver? And what are your thoughts in terms of performance if I were to get lets say a 9kg/8kg FLT-A2 setup?