Hi,

I am currently using the winter months here in New England to upgrade my z for the upcoming autox season. Currently my suspension is stock, and that really needs to change. I have been reading a lot about various coilovers and shock/spring combos, but I haven't really found the information I was looking for. Basically I am trying to choose between a coilover setup and a shock/spring combo. The coilovers I am looking at are the JIC or the HKS RS. As for shocks and springs I am looking for a linear spring with increased stiffness and a moderate drop (less than an 1"). So far I haven't found a spring that really meets that need.

My question is this. What does the extra $1000 I would put into a coilover setup really buy me? Will they really be noticably better for a primarily autox car? If not, and I should go with a spring/shock combo, what combos do people recommend for an autox application? Thanks.

 

Well like drumma02 showed in a recently posted thread the stance triple way adjustables will allow you to adjust compression, rebound, and high speed compression all independently. This can greatly improve the overall handling of your vehicle if setup properly.

In general a coilover can give you a few benefits, larger piston diamter, ability to adjust ride height, and run higher spring rates.

there is a great benefit for any type of racing. your steering response will greatly improve, so for quick turning like in autox it can greatly aid you. you won't feel like you're fighting your steering. you turn the wheel and the car immediately will move in that direction.

these are general statements but should apply to most coils out there.

Rishie

 

Before I can recommend any suspension for you, I'll have to know what class you plan on racing in for autox.

 

Regarding the 350Z:

B Stock: Koni shocks & Cusco solid front sway bar. Hoosier tires.

BSP: I would recommend the Stance coilovers or a Koni shock and aftermarket spring combination. You can add a rear sway as well, and other mods are allowed. Hoosier tires.

BP: Go nucking futs.


One of the worst things about autocross: The 350Z is not eligible in any of the street tire classes. If your region has a Tire class, the 350Z with the mods that I have is a VERY competative car, as Tire class times are based on PAX.

 

Yes but of course. Exactly what Fluid said, if you're driving to compete in a class then look at your class restrictions. If not then just have a good time and setup the car however you want.

your best mod is always to improve driving skill and knowledge more than your mods. I'm always told and a firm believer that driving courses can benefit one a lot more than setting up a car to exceed one's driving skills.

 

I currently don't run in SCCA events. I run mostly in club events which have pretty open classes (basically 2 classes street tire and race tire). If i were going to run SCCA, it would probably be street touring or street prepared.

 

You really haven't found what your looking for because the aftermarket doesn't really delivery a linear spring option that all that stiffer then stock, let along one that is a mild less then one inch drop. Furthermore, oem shock's with springs puts you in the position of having bump travel that is in short supply. I had to abandon my Koni coilover setup because even with 448lbs front rates, and a mild .5" drop, I consistently ran out of bump travel, even with trimmed progressive soft Koni bump stops that were far shorter then even trimmed oem bump stops. Had the Koni's had the ability to adjust stiffer for compression dampning, I might have been able to stay off the bumpstops, maybe.

Here's a list of your linear spring choices.

RSR 350Z linear springs .6”/.6”
Spring rates in LBS 345/417

Hotchkis 350Z Linear springs .6”/.8”
Spring rates in lbs 340/330

Tein H-tech 350z linear springs .3”/.2”
Spring rates in LBS 358/375 (ok, posting with two odd exception's, one Tein say's the front's are progressive, they are not. Two, I tested them and honestly they don't feel as stiff as their spring rates suggest they are).

Tokico D-spec linear springs 1"/1"
Spring rates in lbs 375/375 (stiffest linear setup you can get outside of the Nismo T2 springs)

Swift 350Z linear springs .8”/.6”
Spring rates in LBS 336/364


Whiteline 350Z linear springs (control)
Front: Part # 73219,
Spring rate 365 LBS Drop: .8"-1"
Rear: Part # 73220
Spring rate 445LBS Drop: 1"-1.2"
(sold as 2 front springs and 2 rear springs)
www.whiteline.com.au/store/

Nismo T2 350Z Linear springs 1”/1” drop on 350Z
Spring rates in LBS 625/700
(With how my Koni's behaved at full rebound with 448lbs rates, it would make more sence to run these with better shocks, like TcKline or JRZ)



Which Jic are you consideing? Most here that have Jic have the Flta2, though Jic now offer's their Flta1 series. Flta2's and the RS are at polar opposites with the Flta2 being known as a very harsh riding setup. Key to success is to get the front tires working accross as much of the whole contact patch as you can. IMO, go to the autocross section and work backwards clicking into as many threads as possible and read up on what setup's to you have had the most success.

 

Thanks for the detailed post. Yeah it looks like the shock/spring combo I am looking for doesn't exist. I will probably have to go coilover. I was looking at the JIC FLT2's. I will definitely take a look in the autox section and see what people are using. For you guys who autox, what are you using?

 

You'll have better feedback if one of the mods will kindly move this thread to the auto-x section, where it belongs.

 

...nevermind, stupid question