Gsedan35

iTrader: (10)

The rear oem springs are linear, no wire diameter change, no outside diameter change top to bottom and no coil bind.

The front oem springs are slightly progressive courtesy of a taper in outside diameter top to bottom. The spring rates I got for the car are a average of those differing coil diameters. Because of the design, they're not going to have much spread between intial and final rates and NO coil bind for a sudden change in rate. As a example the Kw coilovers for the Z use the same tapered spring design in the front and have a 525/485 rate

Gsedan35

iTrader: (10)

I would think it would be 65mm springs in the front with Koni coilover conversion parts and 5" ID rear springs, which Swift does also make. Pretty sure 2812's are also colored yellow

DavesZ#3

iTrader: (26)

I'm curious, has anybody tried the TC Kline version of the Koni's with stock springs - for autocross in particular? considering the price, I'm real tempted to buy a set of those instead of the regular SA Konis.

Gsedan35

iTrader: (10)

Not a good idea since they are valved for the Nismo T2 springs which are twice as stiff at 690/690. Yes they are double adjustable, but your only adjusting low speed, high speed rebound and compression cannot be changed without a revalve.

I do know of one member that has the TcKline shocks that is running them with Tein S-techs, not a choice I'd recommend, don't think TcKline or Koni would either I dunno. In case you'd like to pm him.
https://my350z.com/forum/private.php?do=newpm&u=77599

racerbob4

iTrader: (8)

I'm familar with the TC Kline shocks as we used them the first year we raced our T-2 Z car. TC is a long time very respected road racer, both in amatuer races and has driven and fielded teams in pro racing as well. He ran a Z car for one year and came in either second or third at Mid-Ohio Runoffs back about 3 or 4 years ago. He had Koni make these shocks to his design, and take it from me, TC is very good at designing anything for racing. We used them and loved them and for the guy who made this post they are a very economical solution for NASA racing or even SCCA National level racing. We set a couple of track records and had 4 wins on them in the tough Northeast Division. Yes, they were designed for the springs that are listed in the SCCA Touring rules and they work very well with those springs. The only reason we moved to JRZ, which are 3 way adjustable, is we have sponsorship from them and our car and driver responds to very fine adjustments with the car. You do things like that when you are looking for tenths of a second and are at the top of your game. So, my advice is to look at the SCCA specs in Touring, under the 350Z and go with what is offered as its designed to work as an assembly. That includes the adjustable sway bars. Bob

DavesZ#3

iTrader: (26)

Thanks guys. I kinda' had a feeling they were going to be too closely coupled to the T2 springs. I can't change springs and stay in the stock class so I'd better pass on this deal.

Gsedan35

iTrader: (10)

I get the feeling that your JRZ setup is twin tube as well?

Having seen the shock dyno's on the TcKline units, and owning OTS yellows and the Truechoice DA's, the design forces a serious compromise on mid and high speed compression with a attempt to compensate on the rebound side. The curve could be reshaped to try and pull out some low speed and add it to the mid and high speed compression side, but you run into a wall that is the twin tube design, it can only deliver so much. That is why Koni offers the Monotube 2812 for the Z.

Axelerate

iTrader: (19)

The T2 springs look the same as stock. .........



jk of course.

DavesZ#3

iTrader: (26)

I thought they were red and shorter.

stuntman

JRZs are mono-tubes.

Gsedan35

iTrader: (10)

Well two things in play. One,...opps I didn't see the JRZ page links to shocks other then the clubsport, the RS and RS Pro are twin tubes, the race series triple adjustable is clearly monotube, my bad on that. Second, if they were the RS series twin tubes it would go a distance in explaining how the only compelling reason for changing out the TcKline shocks mentioned was because of sponcership. Unless someone bungled the valving on the JRZ's (which I doubt), not much chance you can't point to some differances between the two products as seen on a shock dyno that would make a series case for the switch, differances that aren't as slight as spliting hairs either.