Topic: Spring Rate Comparison GM Vs Aftermarket

[elff]

GM Spring Rates for all Kappa Variations
               
          FE2 LE5 Solstice   FE2 LE5 SKY   FE3 LNF (Non Z0K)   LE5 Z0K Solstice   LNF Z0K Solstice   GM SPO Perf Parts
Front      2.29 Kg/mm        2.29 Kg/mm          3.11 Kg/mm              3.11 Kg/mm            3.77 Kg/mm           3.77 Kg/mm
Rear       3.16 Kg/mm        3.16 Kg/mm          4.08 Kg/mm              4.08 Kg/mm            5.10 Kg/mm           5.10 Kg/mm
 
5 Aftermarket Coilovers vs the Stock GM Springs (in Kg/mm)

         KWs   HKS   B&G   BCs  Elff's BC's  Pedders  FE2 LE5   FE3 LNF   LE5 ZOK  LNF ZOK   GM SPO
Front    7        8        8        7          5              5           2.29         3.11         3.11         3.77          3.77
Rear     5        6        8        7          6              6           3.16         4.08         4.08         5.10          5.10

[miller11386]

Defiantly the best listing for suspension comparison. Thanks for posting this elff!

[Gentleman Jack]

Elff, does miller know you made up all those values? 

[Sol Asylum]

Elff, does miller know you made up all those values?

Of course not and he never will.

[rlhammon]

Thanks, I didn't realize anyone else tracked and logged this stuff!

Curious where you got your numbers from for the aftermarket.  The KW doesn't match what KW told me previously, which is why I'm asking.  They certainly could have changed since I spoke with them, but as with any data... I like to know the source. 

For the record, I believe SOB and I know myself, are still higher than anything posted in this chart.  Also, for anyone wanting to purchase springs, since you'll most likely be purchasing them in lbf/in. here's a handy convertor.

http://www.hraefn.net/projects/spring_rates.php

[elff]

I posted links from 3 sites that sell the KWs in another thread.
All of them listed the springs at
Front 400lbs
Rear 286lbs

Everything was converted to Kg mm because that is how all the aftermarket coilovers were listed.

[ophidia31]

So, looking at those, how do you think a 3.11 in the front and the 5.10 in the rear would be? Ive been thinking about that since I got my le5zoks put on. Bassicaly lef zok up front and lnf zok in back.

[elff]

That would be Too soft for me. 
It does depend on your end game.  Is this for the street or for AutoX/track?

I think that would cause a weird rocking motion over bumps and major oversteer.
Give it a shot and report back.  The more real world feedback we get the better

[ophidia31]

Just tossing out ideas. I was going on the basis of guys running the zok rear and lnf front swya bars and think that the same may go for the spring setup if one were to have both zok sways. It may be good on the track, but like you said, it might not be good on the street with the motion you may get over bumps. Im still running my winter setup because i didnt want to get stuck with a freak snowfall with how cold it was getting up here at night the last few weeks. Looks clear sailing from now on though. Once those softies are off, itll probably tighten up a bit with the stiffer sidwalls of the summers.

And the pedders coilovers are 5kg/mm front and 6kg/mm rear even though i havent seen onyone running them.

[elff]

If you have the hardware, it would be really cool if you could test it and see how it would work.

I'll add those Coilovers to the list

[LatinVenom]

I have the full ZOK setup on my GXP (sway bars front and rear, shocks and springs front and rear) also have the ZOK alignment.
I also have the ProBeam, BackBone and LVKFCB. The car is fine to drive on the street and road coarse.
I do not do Autox so have no idea how it would perform.

[ophidia31]

If you have the hardware, it would be really cool if you could test it and see how it would work.

wish I did. dont have the money to buy the different stuff or tools to pull apart the shock spring setup and switch them out. took my car to the garage so they can do that part of the suspension for me.

[Kelu]

One small correction: Opel GT was ONLY LNF so - only FE3, no  FE2 LE5 SKY/GT

I can't wait to hear your opinion about KW V3.
The problem is you can modify only one compression or bump easily (I can't remember which one), the other one is locate at the bottom of the strut which requires either lifting the car or get under it big time.

Thanks for the info 

[elff]

I updated the first post to remove the GT

[SKY888]

I can't wait to hear your opinion about KW V3.

me too!

[elff]

Who are you asking about the KWs?

[Kelu]

Who are you asking about the KWs?

YOU!!!!

[Sol Asylum]

I think that is one of only two possibilities that Elff hasn't yet tried, you'll have to be patient Kelu.

[Kelu]

I know, that was trying to say

[Sol Asylum]

Actually there may be one more suspension mod I overlooked that Elff might want to try, it involves using oversized bushings.

[elff]

Actually SA, I did try that mod.  It's how I knew they were too big.  As such, I am still rocking the stock Rubber Bushings on the front sway bar.

Kelu
I am not going to be testing the KWs.  I really like the B&Gs.   
The Eibach Sportlines have extremely close Spring Rates to the KWs
I did not like the Eibachs at all.  The rear would bottom out on every drop off.  As such, I think I would not like the KWs for street driving where I live. 
Last
Dave@DDM upgraded the rear springs on the KW3s because they were too soft for their AutoX setup.

[Kelu]

I am not going to be testing the KWs.

Yes you will, I can guarantee that

[elff]

On My Car
TOUCHE!!!!
 

[Sol Asylum]

Have you got the KW on your car Kelu?

[POS VETT]

I thought BC came with standard 7 kg/mm for front and rear.  Mine has 5 kg/mm front and 6 kg/mm rear.