JKS JSPEC suspension kit

No, I didn't. Wasn't thinking about the 934's at the time, but would like to hear his opinion on it.
I plan to do this next year, so if anyone is looking for some 933's on the cheap, let me know so I can get into the 934's ASAP and report back.
 
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From JKS regarding their TJ coils:

Spring rates are 150/200 front and 190/240 rear

Heights are
2" front 19"
2" rear 14.125

3" front 20"
3" rear 15.125"

This took about 10 minutes to get by email.....wish I knew the "secret handshake" it takes to get SAVVY to respond.
 
From JKS regarding their TJ coils:

Spring rates are 150/200 front and 190/240 rear

Heights are
2" front 19"
2" rear 14.125

3" front 20"
3" rear 15.125"

This took about 10 minutes to get by email.....wish I knew the "secret handshake" it takes to get SAVVY to respond.
Thank you sir! I have been trying to locate these specs
 
From JKS regarding their TJ coils:

Spring rates are 150/200 front and 190/240 rear

Heights are
2" front 19"
2" rear 14.125

3" front 20"
3" rear 15.125"

This took about 10 minutes to get by email.....wish I knew the "secret handshake" it takes to get SAVVY to respond.

Can you double check the numbers you got from JKS on that front coil. In the past I got an email from JKS that said it was 150/220 not 200.
 
From JKS regarding their TJ coils:

Spring rates are 150/200 front and 190/240 rear

Heights are
2" front 19"
2" rear 14.125

3" front 20"
3" rear 15.125"
...

For some comparison, assuming JKS and Nth will lift the same Jeep the same amount...

Nth 3" front 20.75" (softer than JKS 3")
Nth 3" rear 14" (stiffer than JKS 3")
 
For some comparison, assuming JKS and Nth will lift the same Jeep the same amount...

Nth 3" front 20.75" (softer than JKS 3")
Nth 3" rear 14" (stiffer than JKS 3")

Splain Lucy?

190/240 rear? If that ain't LJ specific, what is?
 
That is a hellaofa stiff rate for the rear.

Not really, my current BDS are 200lbs. You will be riding in the 190lb section unless you are loaded down. Then you will be glad you have the stiffer rate.
For some comparison, assuming JKS and Nth will lift the same Jeep the same amount...

Nth 3" front 20.75" (softer than JKS 3")
Nth 3" rear 14" (stiffer than JKS 3")

I keep looking at those numbers as well and thought that same thing. I guess we both came away from the coil spring thread with the same thoughts. However, we don't know other things like coil diameter and how tall the soft section is vs the short section. So although I agree with your conclusion, I don't think we know that for sure.
 
Splain Lucy?

190/240 rear? If that ain't LJ specific, what is?

I'm only going off of the free lengths and the advertised lift heights.

I have run two pairs of "LJ specific" coils on my TJ, FWiW. They did/do what I need them to do.
 
Oh to add further information, I had some pms from a guy at jeepforum some time back. He estimated his Nth Degree LJ springs had an initial rate of 147 front and 210 rear. (He calculated that based on the sag of OME and stock springs x their advertised spring rate.) So not 100% reliable either, but it seams reasonable. It also seems very similar to the JKS. I'll bet the Nth TJ rear springs are very similar in rate to the JKS.
 
Not really, my current BDS are 200lbs. You will be riding in the 190lb section unless you are loaded down. Then you will be glad you have the stiffer rate.


I keep looking at those numbers as well and thought that same thing. I guess we both came away from the coil spring thread with the same thoughts. However, we don't know other things like coil diameter and how tall the soft section is vs the short section. So although I agree with your conclusion, I don't think we know that for sure.

I'm struggling with this, being my OME 942's are 160lb in., and hold their own well to being on the stiff side when running light. I think I'm drinking the in./lb rate kool aid brahs.
 
..



I keep looking at those numbers as well and thought that same thing. I guess we both came away from the coil spring thread with the same thoughts. However, we don't know other things like coil diameter and how tall the soft section is vs the short section. So although I agree with your conclusion, I don't think we know that for sure.

I'll go a step further and suggest that the differences between two coils of varying rates that provide the same or very similar ride heights will very difficult if not impossible to distinguish. When I was figuring this out a few years ago, I found that the difference between the softest and stiffest rates on my spreadsheet was about 20%. We simply don't have a very wide range of rates to choose from.
 
Thats the nice thing about OME. The 942s at 160 sound like a good fit for you while I would need the 949s at 216lbs. The JKS at 190/240 seems to straddle that line for an empty jeep and has more support down low to carry weight.
 
For some comparison, assuming JKS and Nth will lift the same Jeep the same amount...

Nth 3" front 20.75" (softer than JKS 3")
Nth 3" rear 14" (stiffer than JKS 3")
You wouldn’t happen to have the spring rates for the Nth 3” springs to add to the uncompressed lengths? I’m compiling data
 
I'll go a step further and suggest that the differences between two coils of varying rates that provide the same or very similar ride heights will very difficult if not impossible to distinguish. When I was figuring this out a few years ago, I found that the difference between the softest and stiffest rates on my spreadsheet was about 20%. We simply don't have a very wide range of rates to choose from.

I don't know, looking at rear springs OME makes rear TJ springs anywhere from 140lbs to 250lbs. Thats a difference of 79%. Obviously they would give you drastically different lift heights on the same Jeep though. But if your static load doesn't change much OME is nice because you really can dial it in. The problem for me and I think others is that our Jeep can change from very light when we are unloaded with the soft top to very heavy when we are fully loaded for a trip with the hardtop. That is the appeal of the Dual rate and progressive rate coil for me.
 
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I'm struggling with this, being my OME 942's are 160lb in., and hold their own well to being on the stiff side when running light. I think I'm drinking the in./lb rate kool aid brahs.
You just need to throw more sh— on your rig brah!
 
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You wouldn’t happen to have the spring rates for the Nth 3” springs to add to the uncompressed lengths? I’m compiling data

Did you see my post above? Nothing official, but one user estimated the initial weight of the front at 147 and the rear at 210lbs. Those figures seam reasonable, but I would take that number with a grain of salt. That was for the LJ specific rear.
 
I don't know, looking at rear springs OME makes rear TJ springs anywhere from 140lbs to 250lbs. Thats a difference of 79%. Obviously they would give you drastically different lift heights on the same Jeep though. ....

The OME 140lb and 250lb springs do not provide the same ride heights.