Spring Rates
 

I am in the market for a set of springs, and its hard to find all the info. I figured i would start a thread so we could have all of the spring rates from each manufacturer in one place in the same format
I'd like to be able to compare those of H&R, Swift, Tein, Eibach and any others.

Brand:
Spring rate
F:
R:
Drop
F:
R:

I am in the Indy car chassis design & tuning industry, and have tested out those 2 springs just for my interest. Your numbers seem to be off a little bit.
Here is the actual numbers converted in Kgf/mm on Roehrig Tester.

Regular
F - 7.5
R - 8.1

Nismo
F - 8.6
R - 9.3

thanks,

what is that in lbs/in

Regular
F - 7.5kgf/mm (419lbs/inch)
R - 8.1kgf/mm (453lbs/inch)

Nismo
F - 8.6kgf/mm (480lbs/inch)
F - 9.3kgf/mm (520lbs/inch)

Tein S:
F: 8.5kgf/mm (476lbs/inch
R: 9.4kgf/mm (526/inch

Drop:
F: -.9"
R: -.7"

Based on the nismo rates, the Tein seem VERY close. i like that. seems like the TEIN with Nismo dampers would be a good match from a longevity perspective. any info on any other brands spring rates?

I have Tanabe NF210, and My struts/shocks seem to be busted or giving me a horrible ride. I just purchased the Nismo shocks, and I am hoping they pair up nicely, but I saw that the spring rates on the Tanabes are a little off from the Nismos. Does anyone have any idea if this will work together?

The spring rates listed for Tanabe are:
F:5.9
R:6.8

I am also having a hard time deciding what springs to go with . I have the S-Tune suspension and want about an inch drop. I kinda want to avoid a rear camber kit so .5 to .75" drop would be ideal. I am leaning on TEIN as well, but I am getting conflicting info. Manufacturer says .8" drop and users are saying up to 1.5" drops!

according to their site the tanabe nf210s are softer than the oem springs (if i am understanding this correctly)
Tanabe:
Front: 5.9kgf/mm
Rear: 6.8kgf/mm

compared to nismo/oem below:

you're probably worse off with the nismo shocks than the OEM, since the nismo shocks are to be paired with a spring that is Firmer than OEM. am i understanding this correctly s30z?

Stock (Regular) F 7.5kg R 8.1kg
Stock (Nismo) F 8.6kg R 9.3kg

Tein S-tech F 8.5kg (-0.9") R 9.4kg (-0.7")

Eibach pro kit F 8.6kg (-0.9") R 9.5kg (-0.8")

H&R Sport F ? (-1.3") R ? (1.0")

Tanabe NF210 F 5.9kg (-0.8") R 6.8kg (-1.0")
Tanabe GF210 F 8.8kg (-0.8") R 9.1kg (-1.0")

Swift Spec-R F 10.0kg (-1.2") R 10.5kg (-1.0")

RS*R Down

15mm drop (0.6") Linear F 8.15 R 8.87

Thanks s30z, you're helping out this thread a lot. so from a longevity perspective, closest to stock will make the shocks last the longest?
if you are like me and looking for a nice drop just for looks, you basically want the closest to OEM spring rate, correct? is it better to go higher or lower than oem? it seems H&R doesn't release their spring rate. i'm really interested in theirs.

i like the idea of those springs b/c they seem like they are a good match for oem, but i feel like the drop is borderline not noticeable. 300+install etc, for .6 inch drop, not sure how i feel.

how does the linear/progressive play into the equation?

Generally speaking, oem shocks (Nismo also) have a good amount of range to stray from the stock spring rates. I would definitely not run Tanabe, because the ride will be over damped.

And Tein on the other hand in my opinion will also be a waste of money on the Nismo shocks. THere will be absolutely no performance gains, it will just be lower.

I have been looking through the forum and I see that Swift would probably be the best bet when they come out. They are relatively stiffer than the Nismo rates and they have dynoed both nismo and stock shocks.

On the chassis that I work on, I like running Swift coilover springs, so material and design wise of their coilover springs at least are unbeatable. I haven't used their lowering spring kits so I really can't say anything about them, but it seems to me like they do a good amount of homework before they release anything.

Again its just my opinion and what I'm probably going to do.

Well I do not want to go stiffer on Nismo struts thats for sure. Its pretty stiff right now. If I could get a spring that is the same as Nismo that is .75" to 1" lower that would be perfect IMHO.

From how I understand it. Progressive is less stiff on the small inconsistencies in the road, (so you get OEM like ride) but once you start to push the car, it stiffens up. (thats why the spring is not evenly coiled) Where Linear is stiff all around and the small inconsistencies in the road will be felt more. (spring will be evenly coiled)

i didnt say i got a 1.5" drop from the springs alone. My tires have a huge role with the drop i have also ... i would say its safe to say the Teins give an approximate drop of inch

it seems like Swift does do the most research on their springs. I am on oem suspension, i dont have a nismo. plus i'm not really looking for performance gains, first and foremost. I'm really just looking to eliminate wheel gap, if i get any performance gains thats a bonus, but i definitely don't want my handling to be worse or to significantly decrease longevity of my shocks.

yea thats what i'm talkin about. i just want a drop, and just like how we aren't ricers that cut our springs to lower our car, we don't want to just throw on some springs that are gonna make our shocks poop out in no time. im' lookin for similar ride quality, just lower look.

ive stated this before but i do not like my TEIN stune shock setup. the ride height is perfect. anything higher and i would just want it lower. even at this height my front camber is -1.6. great for a race car, not for a DD. so yes you will need a camber kit if you want to conserve tires. the rear camber is maxed out. it is barely within factory specs. now as soon as i install 15mm spacers all around i will DEF need a front and rear camber kit!

I did a little bit of research on Swift Spec R springs, and it seems fairly promising. Their are many different factors that come into play when decreasing the life span of a shock. Obviously lowering it to a point will blow them out rather quick. but then I really do not see spring rate affecting the dampers as much as people would think. I mean if you think about it the seals used in a shock valved for a 20kg spring and the seals used in a shock valved for a 6kg spring is the exact same seal. They do not make different reinforced seal for different rates. One of the main reasons why I believe shocks tend to blow with lowering springs is because of the general progressiveness of the spring. Inconsistenties in the rate throughout its stroke. This generally happens with cheaper springs. If you stick a spring like most of the brands out there on a dyno you will see several spikes in the spring rate curve. If I ha to choose something that decreases the lifespan of the shock with lowering not being a part of the factor I believe it is inconsistencies. A shock is a pressurized system and the only way I can imagine a seal leaking is from sudden spikes that the high speed valving cannot quite catch so the low speed valving has to take that impact, affecting the seals.

Now with a little bit of research just right now I have found that even the Spec R for the EVO is very popular as well as the springs for s2000, and because Swift designed them around the OEM shock the springs even though the rates are much stiffer than competitors they are within damping range, and it doesnt seem like anyone is having any problems. And the general consensus is that it is even more comfortable than stock.
http://www.s2ki.com/forums/index.php?showtopic=813701
http://forums.evolutionm.net/evo-tir...g-springs.html
http://forums.evolutionm.net/evo-tir...-comments.html
Obviously even this I would just take with a grain of salt.

Again as I said the Swift race springs are extremely linnear, in fact I can even post up a dyno of one of the springs I have tested for one of the chassis Im building. It almost looks like someone drew this graph out with a ruler.

I hope this helps of if you can even understand it, I am not too much of a writer.

thanks a lot! great info. please do post that graph. so based on what you're saying, the OEM/Nismo springs are most likely linear springs?

nismo springs are linear... Atleast that's all I've ever heard

So what would happen if you installed a set of springs with much lower spring rates on Nismo struts? (Tanabe for instance)

Hate to bump an old thread but are the 2013 sport springs the same as the regular or nismo springs or something in between? I know the window sticker only says sport has euro shocks and nothing about springs.

sub