• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

Can we start a spring stiffness chart type thing?

BIGSLVRXJ

BIGSLVRXJ

NAXJA Forum User
Location
Des Moines, Iowa
Well, I've run my Rubicon Express 3.5" Superflex for about a year now. I've got the RE springs and I've got OME shocks. The thing that boggles me is this. My Jeep rides so stiff, even with the OME shocks, on the street it is horrible. It is pretty much a mallcrawler since the nearest LEGAL offroad spot is like 2 hours away so the street ride is important. My buddy has an XJ that still has stock height shocks on it with a 3" bastardized lift. It has chopped down Rusty's 4" coils (to make them 3") in the front and bastard packs in the back. It rides honestly probably 2 or 3x better than mine does. I know I should quit complaining since I drive a lifted Jeep, it just feels like my Jeep is on a trampoline most of the time. So finally to my question... how stiff are Rubicon Express's springs compared to other companies? Has anyone ever made like a stiffness chart? I'd appreciate any help towards this.
Thanks,
Collin
 
I'll offer this, to start this thread off with a little bit of conflict. :)

RE 5.5" coils start at 22" uncompressed, and go to 17.75" compressed.

Rusty's 6.5" coils start at 21.5" uncompressed, and go to 18.5" compressed.

So RE has a change in length of 4.25", and Rusty has a change of 3", for the same amount of weight (these were installed on the same vehicle).

The advertised values for these springs are 220 lb/in for RE and 180 lb/in for Rusty's. This doesn't match up to the experimental values I posted above, in which the Rusty's ones are stiffer (less compression for a given force).

It's always been my personal opinion (based on trail experience) that vehicles with RE springs tend to be a lot more floppy and show behavior that jives with having soft springs, while Rusty's seems a little stiffer and well-balanced. The measured values I posted confirm this but the advertised values do not.

Thoughts?
 
That's a pretty cool idea. I'm shopping around for springs now for my piecemeal lift, and wouldn't mind having that info before I buy something.
 
OME shocks are stiff as hell. They are great shocks but definately stiff.
I had pro comp es3000 (cheapies) on my 3.5 RE lift & changed to OME Nitro Charger shocks & the thing rode soooooo stiff it nearly rattled my teeth loose on corrigated roads. The cheap shocks were definately a lot softer feeling when just driving around but lacked the control of a nitrogen filled shock when pushed...... just my experience.
 
mattyj074 said:
OME shocks are stiff as hell. They are great shocks but definately stiff.
I had pro comp es3000 (cheapies) on my 3.5 RE lift & changed to OME Nitro Charger shocks & the thing rode soooooo stiff it nearly rattled my teeth loose on corrigated roads. The cheap shocks were definately a lot softer feeling when just driving around but lacked the control of a nitrogen filled shock when pushed...... just my experience.
Click to expand...
See originally I had RE twintubes...I thought they were stiff so I went to OMEs, I noticed almost no difference. The Emus are maybe a touch better, but sure not much.
 
I pulled this from some previous threads in the past:

STOCK, OEM is supposedly 147 lb/in rate. (three different rateings found 125, 148, and 152)

OEM is supposedly 147 lb/in rate.

Tera 4" TJ coils give 4.5" of lift on an XJ and have a 200 lb/in rate , 20.25" tall unloaded
Tera 3" TJ coils give 3.5" of lift on an XJ and have a 170 lb/in rate

Rusty's 4.5" coils give 5" of lift and have a 150 lb/in rate, 22" tall unloaded
Rustys 3" coils give 3" and have 150 lb/in rate.

RE's 4.5" ZJ coils give 6"-6.25" of lift on an XJ and have a 200 lb/in rate, 22" tall unloaded
RE's 5.5" = 220lbs/in per RE
RE's = 180lbs/in per Dave Nay
RE's ZJ 5.5" = 240lbs/in per Crash

Rancho 3" coils, at least the old coils give about 2 1/4" of lift on an XJ and have a very high 235 lb/in
rate.
Rancho 3" = 240lbs/in per Rancho

Skyjacker 8" = 270lbs/in per Crash

OME coils give 2.25" - 2.5" of lift and have a 148 lb/in rate
OME930 front coils: 160lb/in per Kris Anderson
OMEJC1A rear springs: 148 LB/in per Kris Anderson
OMEJC2A rear springs: 137lb/in with 257lb/in overload spring per Kris Anderson
 
Boghog1 said:
I pulled this from some previous threads in the past:

STOCK, OEM is supposedly 147 lb/in rate. (three different rateings found 125, 148, and 152)

OEM is supposedly 147 lb/in rate.

Tera 4" TJ coils give 4.5" of lift on an XJ and have a 200 lb/in rate , 20.25" tall unloaded
Tera 3" TJ coils give 3.5" of lift on an XJ and have a 170 lb/in rate

Rusty's 4.5" coils give 5" of lift and have a 150 lb/in rate, 22" tall unloaded
Rustys 3" coils give 3" and have 150 lb/in rate.

RE's 4.5" ZJ coils give 6"-6.25" of lift on an XJ and have a 200 lb/in rate, 22" tall unloaded
RE's 5.5" = 220lbs/in per RE
RE's = 180lbs/in per Dave Nay
RE's ZJ 5.5" = 240lbs/in per Crash

Rancho 3" coils, at least the old coils give about 2 1/4" of lift on an XJ and have a very high 235 lb/in
rate.
Rancho 3" = 240lbs/in per Rancho

Skyjacker 8" = 270lbs/in per Crash

OME coils give 2.25" - 2.5" of lift and have a 148 lb/in rate
OME930 front coils: 160lb/in per Kris Anderson
OMEJC1A rear springs: 148 LB/in per Kris Anderson
OMEJC2A rear springs: 137lb/in with 257lb/in overload spring per Kris Anderson
Click to expand...
That is exactly what I was looking for. One question though...the stock ratings, is that for the leafs or coils? I'm assuming leafs?
 
my springs are stiffer when its cold out..
and early in the morning :D
 
Wow, a lot of those numbers are REALLY inconsistent.

Check my previous post for just one example:

RE 5.5" coils start at 22" uncompressed, and go to 17.75" compressed.

Rusty's 6.5" coils start at 21.5" uncompressed, and go to 18.5" compressed.

So RE has a change in length of 4.25", and Rusty has a change of 3", for the same amount of weight (these were installed on the same vehicle).

The advertised values for these springs are 220 lb/in for RE and 180 lb/in for Rusty's. This doesn't match up to the experimental values I posted above, in which the Rusty's ones are stiffer (less compression for a given force).
Click to expand...
 
This doesn't help because I don't have the uncompressed length, but the RK 6.5" coils are 17.5" compressed with a 50lb bumper and a Warn winch. And I think they are supposed to be 180in/lb, but I'm not sure.
 
im pretty sure that a 4'' tj spring would only lift an xj 3'', i think tj coils are about an inch shorter to begin with
 
BigBlackHeep said:
Well, I've run my Rubicon Express 3.5" Superflex for about a year now. I've got the RE springs and I've got OME shocks. The thing that boggles me is this. My Jeep rides so stiff, even with the OME shocks, on the street it is horrible. It is pretty much a mallcrawler since the nearest LEGAL offroad spot is like 2 hours away so the street ride is important. My buddy has an XJ that still has stock height shocks on it with a 3" bastardized lift. It has chopped down Rusty's 4" coils (to make them 3") in the front and bastard packs in the back. It rides honestly probably 2 or 3x better than mine does. I know I should quit complaining since I drive a lifted Jeep, it just feels like my Jeep is on a trampoline most of the time. So finally to my question... how stiff are Rubicon Express's springs compared to other companies? Has anyone ever made like a stiffness chart? I'd appreciate any help towards this.
Thanks,
Collin
Click to expand...

Here is another option that I run....Rancho Rockcrawler 4" Competition Springs for the Jeep TJ. The are 160 lbs/in and 20.5 inches long unloaded.

I am at a 3.5 inches lift in the front. They work perfect with my realativly soft Old Man Emu JC1A and OME AAL rear spring packs and JKS shackle.

Curtis
 
In my experience a lot of things can affect the overall ride quality. I bought OME shocks/springs 7 years ago and with stock tires it rode like a dream.

Then I bought TeraFlex LCA's and BFG MT's and installed them at the same time. Suddenly the ride firmed up quite a bit. Was it the stiffer side wall? Was it the fact that the LCA's had a 1 rubber bushing and one poly bushing, when the factory arms had 2 rubber bushings? Do you both have factory control arms and trackbar?

Do your buddy and you have vehicles with identical spring weight? The amount of weight on a given set of springs can change the ride quality. My vehicle with me in it is almost 5000 lbs. Because of the weight up front my OME V8 ZJ springs are too soft and are being replaced.

One other point about OME shocks, they have a comfort series and regular. You could try a set of comfort shocks if you really feel like the shocks are the culprits.
 
vetteboy said:
Then I bought them from you and ran them for two years. :roll:

Ride got better using those IMO, after replacing the OEM's with those and leaving everything constant.
Click to expand...

Yep. I remember that. Too bad your way beyond my hand me downs as I have a few more pieces looking for a good home...

So if it wasn't the LCA's, then it must have been the shoes, I mean tires... :doh:

Never did run a wimpy sidewall tire since those early days and I went to a set of Long Arms that smoothed some of the bumps on the road and off, but never returned the ride quality to what it once was.
 
You must log in or register to reply here.

Similar threads

E
Steering Redo.... Questions before I dive in.
2
Replies
28
Views
1K
RCP Phx
R
I
Bought Son 2000 XJ, Need Help with RC Lift
2 3
Replies
45
Views
6K
Tim_MN
Tim_MN
Root Moose
Mild Lifting with OEM Parts
Replies
12
Views
1K
Tim_MN
Tim_MN
M
New and need help
2 3
Replies
41
Views
9K
Evan03
E
D
First Posting And Sagging Leaf Spring Question
Replies
4
Views
3K
XJ_ranger
XJ_ranger
Back
Top