Spring Rate Effect On Ride Quality

Totally agree. But what I can't figure out is what advantage progressively wound springs offer? I can't write it off as completely a gimic because the new JLs and JTs have progressively wound springs, and the engineers wouldn't waste the effort for no reason.
The stock TJ rear spring is progressive and mounted in such a way to be progressive even further. I suspect that was done to keep the headlights aimed within a parameter regardless of loading. Given that your ass is almost on the rear tire when you are in the driver's seat and the passenger on top of the rear tire, that is the only things I can come up with that justify the effort they went to.
 
Spring rates aren’t going to affect your ride quality on a TJ whatsoever. On a track car, sure, but you can and should forget about spring rate and ride quality when it comes to a TJ. Focus on shocks or ride quality is a concern.
In the dirt bike world, which equates to a bunch of maniacs and only one spring on the rear , it is generally considered the springs coil, diameter, length and rate establish ride height and the shock valving does the work you feel.

My most successful suspension mod is 28 psi, and I also did one called 26 psi. It was even better. Even the bike guys have found creative ways to achieve lower tire pressure, like the Tubliss system...it’s a small inner tube that locks the tire to the bead so the tire is a tubeless rather than traditional inner tune setup . The desert guys go further and then run a hard tire and near no air , as the system becomes an internal beadlock.
 
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Don't lie.

I don’t. Whats the point?

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OME Light Duty 2”
It gave me around 3” front lift and around 2.5” back lift
 
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Hey everyone!

I've read in many threads that springs are there to set your ride height. Shocks, and tire pressure are responsible for your ride quality!

I would like to discuss how much a different spring rate would affect ride quality though.

Theoretically, wouldn't a spring with higher spring rate/ less length would give different ride characteristics than a spring with less spring rate /more length?

The fact that they would be compressed in different rates in the same bumps etc. doesn't mean that there will be a difference in ride quality?

*Of course, the same shocks will be used in both scenarios.
** I know shocks will affect the ride quality more.

@TJim

I've been wondering the same thing, so was glad to see this question go up. I was even wondering whether the answer should impact whether I use spacers to level out my rake, or try to find some longer springs with a similar rate, etc.

Anyway, it sounds like the answer is "Yes, in principle, but no one makes any springs for the TJ with a sufficiently different spring rate that you could really notice". Oh well, but it was a good question.
 
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@TJim

I've been wondering the same thing, so was glad to see this question go up. I was even wondering whether the answer should impact whether I use spacers to level out my rake, or try to find some longer springs with a similar rate, etc.

Anyway, it sounds like the answer is "Yes, in principle, but no one makes any springs for the TJ with a sufficiently different spring rate that you could really notice". Oh well, but it was a good question.
That leads into a good question.

Why should anyone bother using new springs for a 2" lift and not just use spacers?
 
That leads into a good question.

Why should anyone bother using new springs for a 2" lift and not just use spacers?

Well, since this thread is turning into a 'safe space' for newbies like me, I'll say that I think it's because spacers don't compress, and so if you add 2" worth of spacers to your springs, you're losing some of your up-travel. Versus a longer spring with the same rate as the original, which would not compress as far as the original shorter spring, but would still compress further than the original spring with spacers.

Maybe?
 
Well, since this thread is turning into a 'safe space' for newbies like me, I'll say that I think it's because spacers don't compress, and so if you add 2" worth of spacers to your springs, you're losing some of your up-travel. Versus a longer spring with the same rate as the original, which would not compress as far as the original shorter spring, but would still compress further than the original spring with spacers.

Maybe?
I am not 100% sure but I don't think that this is the case. I think for just a 2" lift this problem would not be enough to lose your 4" up travel.

Maybe I'm wrong. I don't know. Maybe someone more experienced will chime in later today!
 
I am not 100% sure but I don't think that this is the case. I think for just a 2" lift this problem would not be enough to lose your 4" up travel.

Maybe I'm wrong. I don't know. Maybe someone more experienced will chime in later today!

Right, I guess if you used spacers, you'd still have the same degree of up-travel as without spacers, because the spring didn't change, and of course it could still compress as much as it did before. But I think that a longer spring (with no spacers) would be able to compress more than the original with spacers could. But again, I'm obviously not sure. Eager to hear what others know, because spacers sure are cheaper than springs ...
 
I am not 100% sure but I don't think that this is the case. I think for just a 2" lift this problem would not be enough to lose your 4" up travel.

Maybe I'm wrong. I don't know. Maybe someone more experienced will chime in later today!
Using a spacer rather than a spring to gain ride height will generally have less up travel and less free length. The higher the ride height, the more this becomes a concern.
 
Using a spacer rather than a spring to gain ride height will generally have less up travel and less free length. The higher the ride height, the more this becomes a concern.
Thats for sure. But what about 2” lift with 4” uptravel
I cant see using a spacer would be a problem to keep a 4” uptravel.

For bigger lifts for sure! The spacer would be too big.

Am I wrong on that?
 
Thats for sure. But what about 2” lift with 4” uptravel
I cant see using a spacer would be a problem to keep a 4” uptravel.

For bigger lifts for sure! The spacer would be too big.

Am I wrong on that?
No idea. When I was messing around with spacers to achieve certain things, I never found a reason for anything over 1.625". But in the end, I quit wasting my time and just used a lift spring with a small spacer to fine tune the rake.
 
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Cool! So @SSTJ was right!

BTW, I would never consider using 2" spacers or bigger.

The only reason I would consider installing a spacer would be for a rake, or a sag because of an winch or something. 10mm - 3/4" max
 
Spacer plus spring increases the block thickness and causes bump spacers.
There is a balancing act that can be played. If the compressed shock length occurs before the spring becomes solid, a spacer can be used to increase ride height to the point where the compressed shock and the solid spring match.
 
There is a balancing act that can be played. If the compressed shock length occurs before the spring becomes solid, a spacer can be used to increase ride height to the point where the compressed shock and the solid spring match.
You, it’s all about making the spring stroke matching the shock stroke, then clearancing
 
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If you want to start understanding what's going on you can look at models of the system. We have gear calculators, so why not others.

Most are simple fixed end mass/spring/damper models. I found this one with a wheel, but it's modeling independent suspension. Jeeps suspensions are tied together side to side by their axles.
https://demonstrations.wolfram.com/SimulatingVehicleSuspensionWithASimplifiedQuarterCarModel/

It never hurts to learn stuff, but as Mr Blaine said, mass is a big factor. Passenger car designers are tuning the damping to get max tire movement without mass movement and after bump frequency. Most old cars rode nice because they were independent suspension and freaking huge boats. When shocks wore out the floated up and down after hitting a bump due to the spring being stronger than the damper. They used mass to get a nice ride not awesome spring and shock technology. So the tire moved more than the mass. Same reason a rowboat and an ocean liner react differently to waves on the ocean.

Raising your Jeep causes added side to side sway when you hit a bump. The solid axle adds mass to the wheel end. So it's never going to ride like a similar vehicle with independent suspension. Lots of variables to address for little gain.

Best ride should be small tires at stock height with softer shocks so the sway is reduced and the tires move the easiest. The new Jeeps are bigger and wider and a more comfortable ride.
 
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