utkinpol

Hi,

what would be most appropriate springs setting for JRZ RS?
i am getting very well respected advice to go with 600/800 but my mechanic says he always keeps springs within 100lbs from each other for 996 cars he built so his opinion was 600/700.

what would make more sense for 997 C2 car? 700# or 800# in rear?

Thanks, Paul.

85Gold

Paul,

On my 996GT3 I ran 550/700 and on the GT2 I run 600/800 as it is heavier in the rear.

Peter

TheOtherEric

In theory, you should calculate the natural frequency in front and in rear, and set the spring rates so that they're equal. I never bothered to do that, and just ran 600/800 like everyone else seems to do. But I strongly suspect that you should really use more like 900+ in the rear when using 600 front. Dunno... run the numbers. But 700 is definitely not right.

Yeah my car is a 993 but pretty similar to 996 in weight, distribution, and maybe? suspension geometry.

utkinpol

thanks, i ordered to get 600/800 dual springs, so, everything should be right i hope.

dacbap

Keep us posted once you have them on and run them, curious?

Rceron

It's too late, but shouldn't any discussion on spring rates always factor in the type of tire (DOT, R-comps, slicks, etc) ? In any case good luck.

utkinpol

well, i do not have trailer so my tire choices are limited. NH and CT tracks are hour and a half drive away, so, it does not let me drive on hoosiers or slicks that far so i have 18" ccw c14 rims set 9" f 12"r.
right now it has beaten up set of toyo r888, next set will be shaved 265/335 kumho v700 if it will fit that I`m not even sure about - will try it today. willalso try to burn them on auto-x, tirerack ha them on sale very cheap, so, it is just an experiment i can afford. if it will fit.
Next set will be toyo RA1 as it is my favorite tire by far but difficult to get these days.
that`s the plan for a track so far. f I will figure out how to bring my tires with me to a track i will get a set of R6 hoosiers.

for auto-x i have different set with hoosiers a6 as Devens is just 35 miles away from me so i can drive there on them.

Bryan at JRZ

A quick introduction: I am Bryan Hise, the JRZ United States rep, working directly for the factory. Thanks for your interest in our suspensions. We're happy to answer any questions you may have.

There are many approaches to specifying the spring rates, ranging from experience to rigorous mathematical analysis. Each of them have valid merits. Generally, we use a combination of all of these while considering the individual's circumstance. For example, sway bars, tires, differential, driver etc. 600/800 has been successful on the 997 C2 with certain setups. Please feel free to PM me for my number if you'd like to discuss it.

Best,

Bryan