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post #16 of 30 Old 09-14-2019, 07:56 AM
1project2many
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Leaf springs can be challenging to work with. I have much experience running and setting up a vintage race car with solid front and rear axle and leaves on every corner. Spring rate tells you how much the springs deflect when a specific amount of force is applied. A thousand lb leaf spring will deflect one inch if 1000 lbs is applied.

We all know leaf springs start with a curve with no load. Then we put them in the vehicle and the vehicle's weight deflects and straightens the curve... some. The springs are designed to be at a certain curve when installed. With either too much or too little curve you lose travel and ride quality. A spring's load rate will tell you how much weight is required to put the springs at the correct amount of curve. A stock vehicle that is usually loaded, say a pickup with a camper in the back, may use a spring with the same spring rate as original but a higher load rate in order to correct the ride height.

What's much harder for an average person to calculate is how the spring responds to terrain. We know that the rate is important. More force required to deflect the spring generally means a rougher ride. But there are other factors. Friction between the leaves is a huge part of how the spring responds. Higher friction resists spring flex and dampens motion which in turn causes force to be transferred to the spring bushings. And yeas, the bushings can also affect spring response. Dry solid bushings resist deflection while soft or lubricated bushings allow more motion. And the angle of the spring shackle affects spring response. As the shackle moves off verticle the effective spring rate decreases. Setting up the vehicle so the shackle becomes vertical as the suspension compresses will make for a rougher riding vehicle. Setting it up so the shackle is vertical before compression will help make for a softer ride.

Many manufacturers have moved away from leaf springs. The complexity of engineering a consistent system is greater than with coils. But it's possible to look at what OE manufacturers who have big money for engineering are doing. And there's a fairly consistent trend developing:

1) Longer springs. Longer springs have a lower rate and conversely will deflect easier.
2) Teflon sliders. Square or round doesn't matter
3) Separate the leaves in the center with metal spacers. By ensuring that only the ends of the leaf contact the leaf above, the amount of friction between leaves is more consistent as the spring flexes.
4) Reduce the number of leaves. A spring with fewer leaves is more responsive.
5) Larger spring bushings. Larger bushings act as dampers to reduce the amount of force transferred from axle to chassis.
6) Run a large, flat "helper" on the bottom to increase spring rate as the vehicle is loaded.

Quote:
I don't share it openly since I feel as if I would be a weasel if I did, even though I'm not obligated.
I've spent a *lot* of time on great forums. I love talking with the smart guys that have inside information. When a person wants to help they can usually find a way to share information without beaing a weasel. It doesn't take long for an average guy to realize what's going on. In large companies product offerings are often driven by profit and loss calculations, and engineering is responsive to marketing rather than the other way around.

Quote:
Problems started to arise when all the copy cat companies came along & used all our hard earned R&D (in the millions $) and then made their springs on our R&D dime.
This happens in the chip tuning world all the time. Tuners spend a pile of time making a kickass calibration then someone else with a small investment in software and hardware copies it and sells it as his own. It doesn't make sense to keep everyone away from the information because this happens. Instead, offer to teach and help. Those that want to DIY will do better. Those that want to pay will pay. And some of the DIY guys will end up buying your product because they appreciate your customer service approach.

Quote:
The fact that there are actually leaf spring rate calculators out there now where you plug in the lengths, thicknesses, and arc numbers to help back out your leaf spring rate kinda makes this secret stuff a whole lot less secret for any copy cat company with half a brain.
The small local spring shops copying springs are not the problem. A loss of a handful of spring sales in a year should not kill a large company. The threat comes from overseas. And I promise that if a Chinese company wants to make a set of springs they will buy a set then measure and copy every dimension they can think of. Leaf springs are not a challenge.
https://www.carscoops.com/2017/11/ch...d-f-150-clone/
http://gmauthority.com/blog/2014/05/...pying-detroit/
https://www.thetruthaboutcars.com/20...evy-precursor/

I am also considering springs for our YJ. I would love to go OME but with a 2" body lift and 30" tires, I think the added lift would look bad. Plus the added height would require my wife, the primary driver, to use a small ladder to climb in and out. So I believe at some point I'm going to contact General Spring to see if their stock height 894 front / 1080 rear springs use sliders. If not I will ask if I can order a set with sliders. And if the answer is no then I will order the springs without and install sliders myself.

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post #17 of 30 Old 09-14-2019, 09:17 AM
RockWoRM
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Originally Posted by Chrisnvegas View Post


Hey, OP. I know what you want and have a solution.

OME spring #37R

OME 37R is OME's lightest duty spring. It's soft and does not lift that much.
When I built a YJ for my kid, I wanted to keep is pretty low but ride the best it could. He was turning 16, get it?

I chose OME 37R. Only marginally higher than stock. Most people can't even tell, yet it is Old Man Emu's softest spring. And man, are they cushy! He is also running 30" tires. We still have the Jeep, the kid is now 20, so we built this Jeep about 5 years ago. The springs have held up well taking my kid thru his TEEN YEARS! NO sag.

I have OME 36R and they are a bit stiffer and quite a bit more lift.

.
OP... X2 this!!!

OME will likely cost a bit more than whatever other springs you're looking at BUT IT WILL BE WORTH IT~!!!!!!
IMHO, don't cheap out on a good set of springs AND shocks. (not saying you're cheap) In a YJ ride is everything. In the long run it pays off.

And just to throw in my $.o2...
Stock springs on a YJ IMO just looks like crap! I hate the look of those almost inverted front springs. No CJ ever looked like that! lol. As in Cris' pic, the OME springs give it a cleaner/more authentic look... for lack of other terminology.



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post #18 of 30 Old 09-15-2019, 07:22 PM Thread Starter
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Quote:
Originally Posted by Chrisnvegas View Post
Hey, OP. I know what you want and have a solution.
OME 37R is OME's lightest duty spring. It's soft and does not lift that much.
Only marginally higher than stock.
This is how your Jeep will look with 4 OME 37Rs and 30" tires...
.
.
.
This is great info, thanks. I had read about the 37R before, does this mean they can use standard shocks?

Regarding knock-off springs...I understand the good companies have R&D and that's why I prefer reputable names. You couldn't pay me to buy Chinese springs, which I suspect are where Crown makes them. Even if the specs are the same.

1988 Jeep Wrangler Laredo
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post #19 of 30 Old 09-15-2019, 08:19 PM
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I would be best to upgrade the shocks too.

But you don't have to break the bank.
On my kid's Jeep I used Skyjacker Hydro 7000 shocks.
Probably the softest shocks without going custom (Fox or King)

I think I paid about 35 bucks each. They come with bushings and red boots. The only complaint I ever heard with those shocks was the paint. In areas that use salt, I guess they rust pretty easy. If that's the case, I'd hang em' and paint em' with something like rustoleum before install. The decals are not applied. So paint them yourself, the apply the decals and boots. I see no reason why they'd rust after that.

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post #20 of 30 Old 09-16-2019, 07:57 AM
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Quote:
Originally Posted by 1project2many View Post
I've spent a *lot* of time on great forums. I love talking with the smart guys that have inside information. When a person wants to help they can usually find a way to share information without beaing a weasel. It doesn't take long for an average guy to realize what's going on. In large companies product offerings are often driven by profit and loss calculations, and engineering is responsive to marketing rather than the other way around.
It's about perception too. While one persons opinion is "he's not being a weasel - he's helping me" and another persons opinion is "he's being a weasel since he and I worked on this exact thing and is now sharing corporate inside knowledge".

When it's viewed from various perspectives, it can be viewed as either helping or hurting.

When you're living, eating, breathing and working long hours for a company, or company of your own for a number of years trying to build it, and then an employee who you pay good money to passes out R&D info, folks can end-up in court. I don't want that to be me.
Quote:
Originally Posted by 1project2many View Post
This happens in the chip tuning world all the time. Tuners spend a pile of time making a kickass calibration then someone else with a small investment in software and hardware copies it and sells it as his own. It doesn't make sense to keep everyone away from the information because this happens. Instead, offer to teach and help. Those that want to DIY will do better. Those that want to pay will pay. And some of the DIY guys will end up buying your product because they appreciate your customer service approach.
Yes, it does make sense or else everybody would openly be publishing their R&D data.
Quote:
Originally Posted by 1project2many View Post
The small local spring shops copying springs are not the problem. A loss of a handful of spring sales in a year should not kill a large company. The threat comes from overseas. And I promise that if a Chinese company wants to make a set of springs they will buy a set then measure and copy every dimension they can think of. Leaf springs are not a challenge.
Perhaps not a large company - however, I have worked on both sides of that scenario.

I helped get Rancho off the ground in the 70's. Keith, Gene & Clarence Shook were (original) owners back then. We made our first million in sales in 1978 and skyrocketed from there. Avery Martinez was their sales manager. Avery & I jumped ship when better opportunities came along (Mickey).

Same can be said for Mickey Thompson's suspension division in Placentia. We started small & rapidly grew to making millions in sales in short order.

James Duff https://www.dufftuff.com/Articles.asp?ID=250 was one of my coworkers too. James & I worked together and helped Mickey win a SEMA award.
Quote:
Originally Posted by 1project2many View Post
I am also considering springs for our YJ. I would love to go OME but with a 2" body lift and 30" tires, I think the added lift would look bad. Plus the added height would require my wife, the primary driver, to use a small ladder to climb in and out. So I believe at some point I'm going to contact General Spring to see if their stock height 894 front / 1080 rear springs use sliders. If not I will ask if I can order a set with sliders. And if the answer is no then I will order the springs without and install sliders myself.
Easy solution - remove the 2" body lift & go OME. Naturally, couple the leafs with a good shock tune.
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post #21 of 30 Old 09-16-2019, 08:44 AM
1project2many
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Quote:
When you're living, eating, breathing and working long hours for a company, or company of your own for a number of years trying to build it, and then an employee who you pay good money to passes out R&D info, folks can end-up in court. I don't want that to be me.
That's understandable. Suspensions and springs are complex subjects and folks who want to make good choices are often left to struggle with minimal guidance. If you see an opportunity to help or to teach in a way that doesn't threaten anyone's security I'm sure it would be appreciated.
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post #22 of 30 Old 09-16-2019, 09:16 AM
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Quote:
Originally Posted by Joe Dillard View Post
It's about perception too. While one persons opinion is "he's not being a weasel - he's helping me" and another persons opinion is "he's being a weasel since he and I worked on this exact thing and is now sharing corporate inside knowledge".

When it's viewed from various perspectives, it can be viewed as either helping or hurting.

When you're living, eating, breathing and working long hours for a company, or company of your own for a number of years trying to build it, and then an employee who you pay good money to passes out R&D info, folks can end-up in court. I don't want that to be me.

Yes, it does make sense or else everybody would openly be publishing their R&D data.

Perhaps not a large company - however, I have worked on both sides of that scenario.

I helped get Rancho off the ground in the 70's. Keith, Gene & Clarence Shook were (original) owners back then. We made our first million in sales in 1978 and skyrocketed from there. Avery Martinez was their sales manager. Avery & I jumped ship when better opportunities came along (Mickey).

Same can be said for Mickey Thompson's suspension division in Placentia. We started small & rapidly grew to making millions in sales in short order.

James Duff https://www.dufftuff.com/Articles.asp?ID=250 was one of my coworkers too. James & I worked together and helped Mickey win a SEMA award.

Easy solution - remove the 2" body lift & go OME. Naturally, couple the leafs with a good shock tune.
Remember Dick Cepek? They used to have off road accessories, lights, lift kits. They had a pretty big store on Industrial Rd. behind Circus Circus back in the 70's and 80's. I know Mickey Thomson somehow ended up with the Dick Cepek name and as far as I know, only has tires now.
What happened to Dick Cepek (the store)
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post #23 of 30 Old 09-16-2019, 09:37 AM
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Yep, I have been doing the moderator thing on 3 different Jeep websites for 20+ years. My shop/garage (5 car garage with lift) is usually open to those local to me although I have worked on a few folks' Jeeps who drove across the US who wanted custom & sometimes 1-off work done. In those type circumstances, I will sometimes teach knowledge, which hopefully turns into understanding.

Here's a small example of something I posted where I attempted to share some knowledge. It's tucked away in the FAQ sticky thread. Perhaps you've seen it before.

I use to build custom shocks as well, from scratch (cut/weld the tubes, machine the pistons, make the reservoirs etc.)

https://www.jeepforum.com/forum/f12/...d-them-623695/
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post #24 of 30 Old 09-16-2019, 09:41 AM
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Yes, I was a tester for Cepek. Tom & I had a few go-arounds. I ran some of their prototype products. They were a competitor of ours for years.
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post #25 of 30 Old 09-16-2019, 09:42 AM
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Originally Posted by Chrisnvegas View Post
OME 37R is OME's lightest duty spring.
The OME CS014F is even softer (148 lbft/in vs. 188 of the 37R). The main difference being the 14's have 4 leaves vs the 36 and 37 which have 5 leaves. I also believe the 36R and 37R have identical spring rates, the 36R is just around 3/4" taller.
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post #26 of 30 Old 09-16-2019, 07:55 PM
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Quote:
Here's a small example of something I posted where I attempted to share some knowledge. It's tucked away in the FAQ sticky thread. Perhaps you've seen it before.
This is the first time I've seen it. Thank you from all that it may have helped.

Quote:
Yep, I have been doing the moderator thing on 3 different Jeep websites for 20+ years.
Hmmm.... Point made. Maybe when mag-lev is the state of the art in suspension we'll get the insider's look at "antique" leaf sprung suspension secrets.
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post #27 of 30 Old 08-10-2020, 08:31 AM
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@Chrisnvegas - did you have to lower the transfer case and put on longer break lines (or any other changes) with the OME spring #37R
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post #28 of 30 Old 08-10-2020, 03:51 PM
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@Chrisnvegas - did you have to lower the transfer case and put on longer break lines (or any other changes) with the OME spring #37R
No. The driveshaft angle was not enough to cause vibration. I did have to change the ujoints. U joints wear-in to the ride height and when that height changes, the joints can vibrate or wear really fast.
The brake lines can easily be relocated to account for the height and increased travel.

Here's a thread detailing how to do it. It's what I did on two of our YJ's and it worked perfectly... and was FREE!
https://www.jeepforum.com/forum/f12/...-yj-s-1421561/

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post #29 of 30 Old 08-10-2020, 07:44 PM
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This thread has really made me rethink something I have for a while. I have the OME 36 and 14 springs IIRC on my 94 roller. It is a 4 cyl and will run 235 or about 29 inch tires. It's intention is DD.


These springs may make 29" tires look stupid but yet I need good ground clearance for big snow drifts and nasty conditions where I live. I have no interest in regearing.

Thinking about sliding the 36 and 14 ome combo to the "zona" jeep which has bigger tires and buying 37 springs for the 94.

If you cannot fix it with a hammer then it has to be an electrical problem.
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post #30 of 30 Old 08-11-2020, 01:15 AM
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Originally Posted by Boojo35 View Post
This thread has really made me rethink something I have for a while. I have the OME 36 and 14 springs IIRC on my 94 roller. It is a 4 cyl and will run 235 or about 29 inch tires. It's intention is DD.


These springs may make 29" tires look stupid but yet I need good ground clearance for big snow drifts and nasty conditions where I live. I have no interest in regearing.

Thinking about sliding the 36 and 14 ome combo to the "zona" jeep which has bigger tires and buying 37 springs for the 94.
You can always experiment and change the spring packs anyway you want.
originally with the 36R's I left the overload spring out. That's the short spring at the bottom of the pack.
Man, you wanna talk about soft. It was so soft it bottomed too easily going over whoops (with a bit of speed)
If your not going over whoops fast...

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