Rep Power: 411

Is there a way to tell what the spring rates are on lowering springs/coilovers. Most manufacturers don't mention it on their site. I know JIC can have custom spring rates or even ones that you can change the spring rate yourself. Thanks.

 
Rep Power: 379

you can have them tested. Problem is, I dont know where. Many co's dont list spring rates because the average person who Purchases Sport/Lowering springs wouldn't know what do do with the Information. The more Reputible Racing suspension companys like H&R, Tein, Eibac, and Neuspeed to name a couple, would be more then happy to tell you the their spring rates, all you have to do is call them and ask.

 
Rep Power: 0

Tein S Tech spring rate:

front/back:
2.8/5.2

 
Rep Power: 379

We under stand LBS/In her in America. Metric tends to confuse us.


157lbs/in front and 291lbs/in on the back. not very stiff at all.

The SS springs are

336lbs/in front and 448 lbs/in back. More then twice as stiff on the front.

 
Rep Power: 416

and its also hard to say with progressive springs since it varies... it gets stiffer n stiffer as it gets compressed more..

 
Rep Power: 0

so, the tein rate is linear or progressive?? & is the ss really doubling the stiffness??

 
Rep Power: 423

Coilovers are linear racing springs, lowering springs are typically progressive.

 
Rep Power: 379

when Racing is involved Linear springs are better to have then Progressive ones. on the street, Progressive will give you a better ride when your just cruzin but still retain some level of performance when pushed.

 
Rep Power: 411

That is why companies like eibach, progress, neuspeed, etc say it is x-x% stiffer than stock. They vary when they are compressed/extended.

 
Rep Power: 298

Conversion Chart. Should be useful for some people.


0 Kg/mm 0 Lb/In
1 Kg/mm 56 Lb/In
2 Kg/mm 111.9 Lb/In
3 Kg/mm 167.9 Lb/In
4 Kg/mm 223.8 Lb/In
5 Kg/mm 279.8 Lb/In
6 Kg/mm 335.7 Lb/In
7 Kg/mm 391.7 Lb/In
8 Kg/mm 447.6 Lb/In
9 Kg/mm 503.6 Lb/In
10 Kg/mm 559.5 Lb/In
11 Kg/mm 615.4 Lb/In
12 Kg/mm 671.4 Lb/In
13 Kg/mm 727.4 Lb/In
14 Kg/mm 783.4 Lb/In
15 Kg/mm 839.2 Lb/In
16 Kg/mm 895.2 Lb/In
17 Kg/mm 951.2 Lb/In
18 Kg/mm 1007.1 Lb/In
19 Kg/mm 1063.2 Lb/In
20 Kg/mm 1119 Lb/In

 
Rep Power: 411

Boilermaker1 gave this awhile ago.

1 lb/in=.017854 kg/mm

 
Rep Power: 379

One of my friends estimated the rate of his springs by measuing the Diamiter of the coil, Simmilar to how you can calculate the rate of an anti-roll bar by knowing its thickness.

I'll ask him about it.

 
Rep Power: 379

Found a Coil spring rate Calculator...

Another (More Informative)

 
Rep Power: 0

neuspeed race springs are 285/400. since they are performance minded springs, are they still progressive like the sports springs?

 
Rep Power: 310

You can tell its a progressive spring if it has dead coils on it. Whereas a linear spring coils are evenly spaced for the most part.

 
Rep Power: 411

most true coilovers are linear springs, most aftermarket springs are progressive. Sleeves are just aftermarket springs on an adjuster so they are usually progressive too. But flotsamm is right.