What is the best riding and performing lift kit for my 2001 TJ?

[freedom_in_4low]

When we get into those contexts, we can have very different conversations, until then, we have to stay in context and that context is very simple.

We have a number of posters in this thread that seem to want to have those different conversations and don't follow the logic of why we can't have them. Is it simply that it's not the context of the original post? Would a new thread titled "best practices in spring selection" be a better place for that conversation?

I can make your rig ride like shit and never touch anything but the shocks. You will not be able to fix one iota of that or affect the ride quality to any humanly discernible degree with anything else you care to change and I don't care what you want to try, it can't be done. That is why once you have them doing their job correctly of holding the rig at design height, springs cease to matter.

I have no disagreement with that, and I'm not picking up that anybody else does. But before you had the springs doing their job of holding the rig at design height, you started with a spring, and why you started with a 100 pound spring with a 20" free length instead of a 300 pound spring with a 13.33" free length (both of which have the exact same ride height) is what I think people are trying to understand, not just that you can tune a shock to work with either one. I think I have an idea (the lighter spring has way more usable travel) but I'd love that conversation to happen so I can learn the other factors involved. Like where would I start if I was suspending a 1/4 midget that looks like it might only need 2" of travel?

 

[mrblaine]

We have a number of posters in this thread that seem to want to have those different conversations and don't follow the logic of why we can't have them. Is it simply that it's not the context of the original post? Would a new thread titled "best practices in spring selection" be a better place for that conversation?



I have no disagreement with that, and I'm not picking up that anybody else does. But before you had the springs doing their job of holding the rig at design height, you started with a spring, and why you started with a 100 pound spring with a 20" free length instead of a 300 pound spring with a 13.33" free length (both of which have the exact same ride height) is what I think people are trying to understand, not just that you can tune a shock to work with either one. I think I have an idea (the lighter spring has way more usable travel) but I'd love that conversation to happen so I can learn the other factors involved. Like where would I start if I was suspending a 1/4 midget that looks like it might only need 2" of travel?

Again, this all goes back to the "hey, my rig rides too harsh, what is the best riding spring?" It doesn't fucking matter, it it isn't the god damn spring.

 

[Mr. Bills]

Again, this all goes back to the "hey, my rig rides too harsh, what is the best riding spring?"

Change the inflection slightly and one's perspective a bit and the answer to that question becomes quite simple:

 

[Rubicon John]

Would a YJ with leafs and perfectly matched shocks ride worse than a YJ with coil springs and perfectly matched shocks?

Wrong context?

 

[jesseshoots]

Would a YJ with leafs and perfectly matched shocks ride worse than a YJ with coil springs and perfectly matched shocks?

Wrong context?

Completely different animal. When switching from leafs to coils you have to add control arms.

 

[Fargo]

We have a number of posters in this thread that seem to want to have those different conversations and don't follow the logic of why we can't have them. Is it simply that it's not the context of the original post? Would a new thread titled "best practices in spring selection" be a better place for that conversation?



I have no disagreement with that, and I'm not picking up that anybody else does. But before you had the springs doing their job of holding the rig at design height, you started with a spring, and why you started with a 100 pound spring with a 20" free length instead of a 300 pound spring with a 13.33" free length (both of which have the exact same ride height) is what I think people are trying to understand, not just that you can tune a shock to work with either one. I think I have an idea (the lighter spring has way more usable travel) but I'd love that conversation to happen so I can learn the other factors involved. Like where would I start if I was suspending a 1/4 midget that looks like it might only need 2" of travel?

I would love to see Mr. Blaine start this new post for two reasons.

1) I know how much he hates these conversations, and gets frustrated with guys like me, yet he is always here trying to help us understand. So the irony of him actually starting the post would just be too rich not to want to see him start the post.

2) On a sincere note, I think much of the confusion does stem from our lack of understanding of how Mr Blaine and others choose their springs and why. I think he has touched on it a couple of times through out this thread, but I still find it confusing that he goes to such great lenghts to find the proper spring at the begginning of each build, but then tells us spring rate doesn't matter. I understand that any spring can be tuned for with the proper shock. But clearly having the correct spring right from the beginning helps.

In addition to how he chooses his springs, I wonder if there could be comments on any exceptions to the rules. Such as in my case where I will occasionally load up my family with camping gear and the weight of my Jeep changes drastically. In that case, it seems to me you have a choice of getting springs to carry the load and it rides bad empty (like a pickup) or you build it for empty knowing you will be on bumpstops as you travel to your destination. Or can you build something that fits somewhere in between (That might just suck at everything?). Do any of the dual rate springs help for this task? I have JKS dual rates on order just to try this out. The 'ride rate' is nearly identical to my current BDS spring rates. So rates between the two coils are irrellevant until I get to the firm bottom rate. It will be interesting for me to see.

 

[freedom_in_4low]

In addition to how he chooses his springs, I wonder if there could be comments on any exceptions to the rules. Such as in my case where I will occasionally load up my family with camping gear and the weight of my Jeep changes drastically. In that case, it seems to me you have a choice of getting springs to carry the load and it rides bad empty (like a pickup) or you build it for empty knowing you will be on bumpstops as you travel to your destination. Or can you build something that fits somewhere in between (That might just suck at everything?). Do any of the dual rate springs help for this task? I have JKS dual rates on order just to try this out. The 'ride rate' is nearly identical to my current BDS spring rates. So rates between the two coils are irrellevant until I get to the firm bottom rate. It will be interesting for me to see.

I think in a case like yours, the answer would be heavier springs. They would sag less in response to the increase in load, so it would have less impact to your travel bias. Dual rate gets you the heavier springs for minimizing ride height response to load variation, without compromising as much on free length and usable travel.

I'm in the same boat. Most of the time I'm in a soft top and doorless, but I've got a wife and two kids, and when we travel I throw a cargo carrier on the trailer hitch along with full doors - I'm guessing probably 500 extra pounds all added up. I'm supposed to have some aluminum trail doors on the way which will help. Fortunately the extra load usually happens during soft top season and not when I have a 140lb hard top on as well.

I don't even know what my springs are. They came on the Jeep and give about 2.5" lift with the soft top. I put 3/4" spacers on them to fix my travel bias.

 

[cac90277]

That is the equivalent of putting roughly 2-4000 lb. per inch springs on each corner of a TJ if your 150 and 160 numbers were accurate.

That completely makes sense.

 

[cac90277]

Yeah, these were good times. Seems long ago, he just graduated high school this year.

 

[Daz7]

I've been told same thing.. that spring rates can affect body roll...

Yes, along with handling characteristics. The table below gives a rough overview of how you can alter handling characteristics by deliberately altering specific items to get a desired outcome. Whilst a lot of this isn't relevant with a 4wd vehicle it does give you a rough idea on how changes can affect handling. We've setup race cars by altering spring lb'age to get to a certain point and then relied on both sway bar and shock adjustments to fine tune to different circuits.

However, your TJ is really agricultural and basic with huge unsprung weights and wheel travel compared to a sports car.

Bottom line with this ongoing discussion. These guys are finding springs don't alter much, because the small changes in 'off the shelf springs' lb'age isn't enough to see or feel change in a TJ. Whilst in a sports car you probably would see change when looking at say a 50-70lb spring rate alteration..

So my question is, if we aren't seeing a lot of change between off the shelf springs, if a TJ owner wants a 3.5" lift the forum would recommend using Metalcloak springs going forward?

Here's the pretty picture of stuff that's not relevant.

 

[BuildBreakRepeat]

So my question is, if we aren't seeing a lot of change between off the shelf springs, if a TJ owner wants a 3.5" lift the forum would recommend using Metalcloak springs going forward?

No. Due to the longer bumpstop extensions needed due to the coil stacking at the top. Free length is good though.

 

[Fargo]

No. Due to the longer bumpstop extensions needed due to the coil stacking at the top. Free length is good though.

If I understand MrBlaine correctly, which there is a chance I don't, this is what his focus is on when selecting springs. He wants to make sure they are long enough to not come loose at full extension and they are short enough to compress fully inside the bumpstop. You don't want your spring to be the limiting factor in setting your bumpstops. I fully agree with this. After that, I'm not sure MrBlaine and I would choose the same spring. I guess from there you pick the rate and length that gives you the height you want.

 

[BuildBreakRepeat]

If I understand MrBlaine correctly, which there is a chance I don't, this is what his focus is on when selecting springs. He wants to make sure they are long enough to not come loose at full extension and they are short enough to compress fully inside the bumpstop. You don't want your spring to be the limiting factor in setting your bumpstops. I fully agree with this. After that, I'm not sure MrBlaine and I would choose the same spring. I guess from there you pick the rate and length that gives you the height you want.

From my understanding, the constraints that fit a long free length, short compressed length, and provide a set ride height limit the selection to one or maybe 2 springs. That’s because in order to get a long and light spring that provides a specific ride height, the lbs/in is very narrow that work. I’m not talking about coil overs in the above stuff due to 99% not running them.

 

[Daz7]

That’s because in order to get a long and light spring that provides a specific ride height, the lbs/in is very narrow that work.

No, theres more than likely a wider range of lb'ages in a TJ that will feel similar because of the vehicle. I did read on some TJ forum where someone was quizzing about a 20-30lb difference in spring rates. You'd never notice it.

 

[jjvw]

If I understand MrBlaine correctly, which there is a chance I don't, this is what his focus is on when selecting springs. He wants to make sure they are long enough to not come loose at full extension and they are short enough to compress fully inside the bumpstop. You don't want your spring to be the limiting factor in setting your bumpstops. I fully agree with this. After that, I'm not sure MrBlaine and I would choose the same spring. I guess from there you pick the rate and length that gives you the height you want.

You are describing a spring that closely matches the shock travel. In the case of outboarded and relocated shock mounts to increase travel, that points to the longest lightest spring that provides the desired ride height.

Why do so many of us build our shocks around the Currie 4"? What happens to someone building a fat heavy rig where a higher spring rate is needed to provide the same ride height as Currie?

 

[Daz7]

I wonder if there could be comments on any exceptions to the rules. Such as in my case where I will occasionally load up my family with camping gear and the weight of my Jeep changes drastically. In that case, it seems to me you have a choice of getting springs to carry the load and it rides bad empty (like a pickup) or you build it for empty knowing you will be on bumpstops as you travel to your destination.

I hate to say it as I dislike them but have you considered airbags for the rear?

I'm not a fan but know a few people using them in Wranglers. Left at 5psi normally they do nothing but with a load or trailer hitched it gives you some adjustability.

 

[Fargo]

From my understanding, the constraints that fit a long free length, short compressed length, and provide a set ride height limit the selection to one or maybe 2 springs. That’s because in order to get a long and light spring that provides a specific ride height, the lbs/in is very narrow that work. I’m not talking about coil overs in the above stuff due to 99% not running them.

Your desired ride height and extended shock length will greatly affect your spring choices using the criteria above. The guy that wants a 2" lift and never disconnects his swaybar won't have issues finding a spring long enough. The guy that wants a 4" lift and maximum flex will be looking at a very different set of springs.

 

[jjvw]

Your desired ride height and extended shock length will greatly affect your spring choices using the criteria above. The guy that wants a 2" lift and never disconnects his swaybar won't have issues finding a spring long enough. The guy that wants a 4" lift and maximum flex will be looking at a very different set of springs.

Either way, those two guys are looking for a spring that provides a desired ride height.

 

[Fargo]

I hate to say it as I dislike them but have you considered airbags for the rear?

I'm not a fan but know a few people using them in Wranglers. Left at 5psi normally they do nothing but with a load or trailer hitched it gives you some adjustability.

I considered them. I have them in my Pathfinder for the same reason. They help, but as I feared, the fittings eventually started to leak. I also had concerns regarding the LJs bumpstops being under the airbag. I would consider them for a JK or JL that has the bumpstops located outside of the spring.

 

[jjvw]

I ran bags in mine for several years. There is no issue running them under the factory bump stops. Extend the bumps as you normally would. Keep the jounces and size the deflated bag to fit between the jounce and axle pad at the desired ride height. I also ran mine empty through an open bleed valve when not in use.