Rough ride

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Good point. So, if we can clearly demonstrate that this is true with OME coils, we really cannot say it is true with ALL coils then can we? The best we can say is it is true with SOME coils that people have used. I know how it sounds, but that doesn't change the facts.

I question whether you can you really demonstrate it with OME coils, or you are maybe observing something else. Because there are others that have demonstrated (and very convincingly so) otherwise with other coils in a very controlled manner, where the ONLY thing that is changing is spring rate.
 
Linear rate springs like OME, BDS, RE, etc, all work the same way. And they can all be calculated the same way. Even the allegedly dual, triple, quadruple rate coils are really just linear rate coils wound with tighter sections. The wire diameter is consistent throughout. And most don't transition between wound sections during normal driving.

The bottom line is that Old Man Emu coils are not unique or magical. The only thing they have over other brands is a broader range of rates and lengths that allow for some more nuance in selecting a lift height in the 0-3" range on a TJ.

Before making assumptions regarding OME coils and why they offer different rates, perhaps you should contact their engineering people in AUS and ask them about it.

Lighter rate coils are designed for lighter loads. Thus, the free standing height of the coil is shorter to fall into that 2" to 2.5" average that we see from these coils. As you go higher in spring rate, it is assumed that the jeep will be carrying more weight, so the free standing height of the coils is taller to bring it into that height range again. The point is that they do not make various coil rates simply to achieve different lift heights. Their own literature shows heavier spring rates are designed in proportion with weight added to the vehicle.

Again, I really don't know there would be any question about this. Lighter rate coils are designed to carry lighter loads. Progressively higher spring rates are designed to carry progressively heavier loads.
 
Again, I really don't know there would be any question about this. Lighter rate coils are designed to carry lighter loads. Progressively higher spring rates are designed to carry progressively heavier loads.

That is not the question we are discussing.

The question is - if you set up two jeeps at nearly the same ride height with two different coils (OME or otherwise) that are differing in rate say by 20 lb/in, with nothing else being different, will you be able to tell the difference in ride quality? The answer here is no. But I think you seem to disagree with that.
 
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Before making assumptions regarding OME coils and why they offer different rates, perhaps you should contact their engineering people in AUS and ask them about it.

Lighter rate coils are designed for lighter loads. Thus, the free standing height of the coil is shorter to fall into that 2" to 2.5" average that we see from these coils. As you go higher in spring rate, it is assumed that the jeep will be carrying more weight, so the free standing height of the coils is taller to bring it into that height range again. The point is that they do not make various coil rates simply to achieve different lift heights. Their own literature shows heavier spring rates are designed in proportion with weight added to the vehicle.

Again, I really don't know there would be any question about this. Lighter rate coils are designed to carry lighter loads. Progressively higher spring rates are designed to carry progressively heavier loads.

Did you see my two example charts? I'm quite familiar with how rate and free length affect the ride height based on the sprung weights. I am also familiar with using small spacers to adjust ride heights and to utilize a longer lighter rate coil for a taller lift height.

I go back to the gas tank question. How many of your customers can tell the tank is empty based on feel alone?
 
The facts are that even with your examples, the ride height changes. And the fact remains that with low amounts of up travel, as found on LCoG builds, a small change in ride height can make the difference between running into the jounces or not. And that is before running into full shock compression. All of this is changing the ride quality more dramatically than any spring rate change that isn't overshadowed by filling an empty gas tank.

How many of your customers can tell by feel alone that the gas tank is empty?

OME lifts are low COG products- at least compared to 4" to 6" lifts. As such they are designed to work that way. They are still taller than the OE suspension, so do all stock wrangler owners complain about bottoming out the shocks or hitting the bumpstops? Wouldn't that mean that the OEM suspension was designed completely wrong on every jeep and they would all be non-drivable? Are there not scores of stock wrangler owners that are happy with their suspension and have no complaints about it bottoming out?

Sure, if the shocks are way too long or the bumpstops are too long or the springs are too soft, you can bottom out any suspension. If the overall set up is done correctly, it's a non-issue.
 
That is not the question we are discussing.

The question is - if you set up two jeeps at nearly the same ride height with two different coils (OME or otherwise) that are differing in rate say by 20 lb/in, with nothing else being different, will you be able to tell the difference in ride quality? The answer here is no. But I think you seem to disagree with that.

I don't seem to disagree with that, I absolutely disagree with that- and yes, I am speaking about OME coils specifically.

You say the answer to a 20lb spring rate difference is no. I would submit to you that your answer is based on PURE speculation based on the experiences of others here. Let me ask you- How many different OME coils have YOU installed on a TJ (without changing anything else) to come up with your answer?
 
Did you see my two example charts? I'm quite familiar with how rate and free length affect the ride height based on the sprung weights. I am also familiar with using small spacers to adjust ride heights and to utilize a longer lighter rate coil for a taller lift height.

I go back to the gas tank question. How many of your customers can tell the tank is empty based on feel alone?

So, did you install all of the coils in those charts in the same jeep and drive it?

To answer your question- no. Most people will not notice the difference between an empty and full gas tank. So what?
My point was- and is- that a change in OME coils will make a noticeable difference in RIDE quality on the exact same jeep.

If an OME equipped TJ rides rough, a softer OME coil will ride better. If a softer sprung TJ is good, but a heavy bumper and winch is added later, the jeep will benefit from a firmer rate to carry the added weight better and maintain the ride it had before.
 
OME lifts are low COG products- at least compared to 4" to 6" lifts. As such they are designed to work that way. They are still taller than the OE suspension, so do all stock wrangler owners complain about bottoming out the shocks or hitting the bumpstops? Wouldn't that mean that the OEM suspension was designed completely wrong on every jeep and they would all be non-drivable? Are there not scores of stock wrangler owners that are happy with their suspension and have no complaints about it bottoming out?

Sure, if the shocks are way too long or the bumpstops are too long or the springs are too soft, you can bottom out any suspension. If the overall set up is done correctly, it's a non-issue.

Fundamentally, I reject the LCoG build philosophy. And nowhere did I say that all stock Wrangler drivers have undrivable Jeeps.

The assertion is that you cannot swap springs without changing the ride height one way or the other. Changing the ride height changes how the shock behaves by changing it's travel bias. And changing the ride height on a shorter travel shock is going to have a greater significance, for better or worse, than the same ride height change on a longer travel shock.
 
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So, did you install all of the coils in those charts in the same jeep and drive it?

To answer your question- no. Most people will not notice the difference between an empty and full gas tank. So what?
My point was- and is- that a change in OME coils will make a noticeable difference in RIDE quality on the exact same jeep.

If an OME equipped TJ rides rough, a softer OME coil will ride better. If a softer sprung TJ is good, but a heavy bumper and winch is added later, the jeep will benefit from a firmer rate to carry the added weight better and maintain the ride it had before.

pardon my ignorance to OME springs but let's say i want 2.5" of suspension lift.. how many coils does OME offer for me to get that ride height, not changing anything other than the coils to achieve 2.5"?
 
So, did you install all of the coils in those charts in the same jeep and drive it?

To answer your question- no. Most people will not notice the difference between an empty and full gas tank. So what?
My point was- and is- that a change in OME coils will make a noticeable difference in RIDE quality on the exact same jeep.

If an OME equipped TJ rides rough, a softer OME coil will ride better. If a softer sprung TJ is good, but a heavy bumper and winch is added later, the jeep will benefit from a firmer rate to carry the added weight better and maintain the ride it had before.

I've been through more OME coils and spacers than most here. If there was ever a difference in ride, it was exceedingly minor if it even existed to begin with.

@Irun has a post earlier in this thread with similar conclusions. Take a look and comment on it.

I have also done the shock work and have had the tuning to know first hand that shocks have an enormous affect on the ride quality. Right now, I can adjust my shocks to be excessively soft and cloud like or harsh and jittery. I have used many different springs, and never had the difference in ride quality between them that a change in shock can do.

A full tank of gas is about 90lbs, btw. That's about 45lbs difference for one of the rear springs to react against. On a stockish rate pair of coils, this translates to about a 3/8" difference in ride height. If your clients can't tell the difference if a 3/8" change in ride height by adding 90lbs of fuel, they aren't perceiving a change in ride quality after a 20lb x2 change in spring rate. If it exists, it isn't coming from the spring rate.
 
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I don't seem to disagree with that, I absolutely disagree with that- and yes, I am speaking about OME coils specifically.

You say the answer to a 20lb spring rate difference is no. I would submit to you that your answer is based on PURE speculation based on the experiences of others here. Let me ask you- How many different OME coils have YOU installed on a TJ (without changing anything else) to come up with your answer?

I don't need to touch the fire 1000 times to know it's hot. I can understand it from other people's experiences equally well. It's not the case always and there are things for which direct experience helps more than inferred knowledge, but this situation with springs is not one of those.

If you can, please clearly explain what it is about OME springs that are very special, other than the fact that they are offered in multiple rates and different lengths. I have already postulated that they are not different than offerings any other manufacturer except in terms of the very exact numbers they offer and I stand by it.

And a question for you - how many jeeps have you worked with that had tuned shocks, good or bad? And yes, this is absolutely one of those situations where direct experience will teach more than inferred knowledge. I know because I have experienced it, and I know others that have experienced the same.

If you have not experienced it, it'll will be very useful for you to find a Jeep amidst the many you may know in the community and go experience how much difference changing the shock tune (note: I did not say changing the shock - I said changing only the tune in the shock) makes by itself. Then please come back and tell us if you still think spring rates in the range that we can get for our TJs for any given height matter.
 
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Unless you’ve built your reputation around being the go to guy for OME lifts. 😉

Where does it say that one cannot be in the industry and be correct about a product or concept? I understand that many shops make recommendations based on profit margins or other factors. Anyone that knows margins knows that OME products are not where the money is. They are legendary in the jeep and toyota markets for world class suspension systems that are known for optimum ride, handling and performance in the smaller lift arena.

Let me ask you this. If you want to know about Old man Emu suspensions, wouldn't you go the people that have the most hands-on experience with the product? If there's someone who's installed and tested more OME suspension set-ups on a TJ, who cares whether they are in the business or a hobbyist/enthusiast?
 
Where does it say that one cannot be in the industry and be correct about a product or concept? I understand that many shops make recommendations based on profit margins or other factors. Anyone that knows margins knows that OME products are not where the money is. They are legendary in the jeep and toyota markets for world class suspension systems that are known for optimum ride, handling and performance in the smaller lift arena.

Let me ask you this. If you want to know about Old man Emu suspensions, wouldn't you go the people that have the most hands-on experience with the product? If there's someone who's installed and tested more OME suspension set-ups on a TJ, who cares whether they are in the business or a hobbyist/enthusiast?

any chance i can get my question answered? i'll ask it again so you don't have to search:

pardon my ignorance to OME springs but let's say i want 2.5" of suspension lift.. how many coils does OME offer for me to get that ride height, not changing anything other than the coils to achieve 2.5"?
 
I have run a bunch of different springs and different shocks, including OME's. I've experimented with "bolt in" shocks probably more than most, including running my jeep without shocks for knowledge sake. I also don't believe the springs available for a TJ in a given lift will make a difference in ride. The springs have TWO jobs...to support the body of the vehicle at a given height and to provide compliance between the body and axles/tires. The compliance allows the unsprung weight to move in relation to the Sprung weight. Supporting the vehicle is simply making sure that the spring has enough "force" to keep the corner weights at the "proper" height. What doesn't get talked about enough is the precise lift height of springs. Like @jjvw said, a full tank of gas will influence lift height. So, the lift heights stated for a particular set of springs is an average. 2.5" OME springs might be 2 inches on one rig and 3" on another (or 4 in the case of one member a few years ago).

Springs, when you get right down to it, have a pretty finite design window. They need to be able to cycle indefinitely, which means there is a limit to the amount of stress and strain you can induce into the material. Too much and the spring will never compress. Too Little, and the forces will exceed the yield strength of the material and it will take a permanent set. Further there are fatigue concerns to worry about...so you reduce the design window even further. Therefore..springs designed for the TJ are going to be of a VERY similar design...no matter what. They HAVE to be, simply because people won't accept a spring with a 50,000 mile limit.

Knowing all that...Springs can't possibly affect ride quality. They are going to all be so similar as to not make a difference. I do think that people will misattribute other characteristics of ride quality to springs though. I know a LOT of people that have never cycled their suspension to know what is contacting first and what might be contacting hard. Those people will change springs and attribute the change in springs to "fixing" one of those other issues, erroneously. What really got fixed is the travel bias.
 
If an OME equipped TJ rides rough, a softer OME coil will ride better.

Try this ^^^ experiment by removing the shocks and take a nice easy drive down the road with a 2349OME coil and then a 2943OME coil. Tell us what you find out. Then for more fun swap in a 2940OME and a BDS034308. Tell us what you find out. Most importantly, do it blind so you don't know what spring is in there. Tell us what you find out.
 
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Help me out, I have read that spring frequency has something to do with shocks and ride. Did I miss something or were these guys wrong?

The long answer is yes and the short answer is no. If you are purchasing coils as a set from a reputable manufacturer then ideally that will have been accounted for as best as possible. There was a problem years ago with a couple lift companies that did not get the rate spilt correct and you quickly knew something was wrong because the rear would slam going over things like speed bumps.
 
any chance i can get my question answered? i'll ask it again so you don't have to search:

pardon my ignorance to OME springs but let's say i want 2.5" of suspension lift.. how many coils does OME offer for me to get that ride height, not changing anything other than the coils to achieve 2.5"?

That can't be answered without knowing something about the sprung weight of your Jeep. But I can tell you that ~2.5" of lift on a TJ is typically reaching the limits of what OME can do on a TJ. This doesn't include the OME 4" springs which are an odd spring design in the realm of that lift height.
 
Get yourself a tape measure.

From the factory, the rear spring should measure about 8" tall as the Jeep sits in the garage. The exposed shock shaft under the red boot should be about 3.5-4" inches. Someone else can talk to you about the Rancho 5000 shocks.

Thanks. I’ll do it
 
That can't be answered without knowing something about the sprung weight of your Jeep. But I can tell you that ~2.5" of lift on a TJ is reaching the limits of what OME can do on a TJ. This doesn't include the OME 4" springs which are an odd spring design in the realm of that lift height.

it definitely can be answered without knowing the sprung weight of my jeep: do they manufacture 2 different spring rated springs that give the same exact ride height? the answer is no.

follow up question being how do i make my ride softer or firmer with that singular option?
 
it definitely can be answered without knowing the sprung weight of my jeep: do they manufacture 2 different spring rated springs that give the same exact ride height? the answer is no.

follow up question being how do i make my ride softer or firmer with that singular option?

No they don't manufacture two different spring rates that give the exact same ride heights on the same Jeeps out on the mass market, except for that one highly specific one in a specific someone's garage where they did create two sets of springs with two different rates and lengths where the Jeep weight results in the same ride height between the two sets of springs.

If you look hard enough, you can find these different springs, sometimes from different manufacturers, that will provide near identical ride heights at a specific sprung weight. Change the weight and you might find an entirely different set of springs that do this. It actually an interesting curiosity when you do find these.
 
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