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And thanks...this just reiterates my thinking that Im going to have to go over every bolt to see if he torqued them properly.
 

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Bumpstops ordered from performance, will trim down to whatever size I need.

I just want to do this properly and one time so i can move onto other things going on.
 

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Thanks for the informative thread, I just installed a "pieced together" lift kit and did an initial measurement for bump stops tonight, but my numbers don't seem right.

I installed:
Curry 4" springs (lifted 4" front, and 5" in the rear, waiting to see if it settles any more but may change these for something else).
Rancho 9000XL 255 front shocks (25.9” extended / 15.9” compressed)
Rancho 9000XL 256 rear shocks (24.2” extended / 15.3” compressed)
RE Superflex Adjustable Upper and Solid Lower Control Arms, RE front track bar, RE rear track bar bracket

With full weight on the axle and all parts installed, I just measured the distance of the shock to be fully compressed vs. the distance between solid bumps on the spring perches. Here's what I came up with:

Drivers Front: 5 1/8" shock, 9 1/8" spring
Passenger Front: 5" shock, 9" spring
(4"+ bump stop required??)

Drivers Rear: 7 3/8" shock, 10 1/4"-10 3/4" spring (angled upper perch, shortest and tallest point)
Passenger Rear: 7 1/8" shock, 9 3/4"-10 1/2" spring
(3" bump stop required?)

These seem like they require too much bump stop, I asked quite a few people for recommendations on matching the spring and shock lengths so they would be paired well, I hope that they are and that I'm missing something here.
I haven't driven on this since installing some of the components so after a drive tomorrow I will measure again, but those distances should increase/decrease in a linear way so the difference should stay the same.

Any thoughts? Thanks...

edit: I measured these two distances, from solid cup at the top to solid center 'perch' at the bottom, not including the factory bump stop (but the Rancho 9000XL doesn't have a rubber 'bump stop' in it like what is pictured here:
 

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Rancho 9000XL 255 front shocks (25.9” extended / 15.9” compressed)
Rancho 9000XL 256 rear shocks (24.2” extended / 15.3” compressed)
....
Drivers Front: 5 1/8" shock, 9 1/8" spring
Passenger Front: 5" shock, 9" spring
(4"+ bump stop required??)

Drivers Rear: 7 3/8" shock, 10 1/4"-10 3/4" spring (angled upper perch, shortest and tallest point)
Passenger Rear: 7 1/8" shock, 9 3/4"-10 1/2" spring
(3" bump stop required?)
front will need ~2.5" extension: 16" - 13.5" (max w/o extension) = ~2.5"
rear will need ~3" extension: 15.3" - 12.25" (stock) = 3.05"

seems fairly reasonable for 4" of lift. you'll still need to push things to full bump to get the real numbers & check clearances.
 

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Thank you for the response, I did read your suggestions in the first post and you seem like you know this stuff well enough that I can just blindly follow your suggestions, but I really like to learn and understand things as I go, so do you mind explaining why its not important to work off of the two measurements that I took? It makes sense to me that if the spring perches have 9" between them and the shock can only compress 5" then I have to limit the spring travel by 4" to make sure not to over-compress the shock. Is there something that I'm missing with that way of thinking?

Thanks for the help!
 

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Other things can hit before your shocks bottom out. Frankly, it is simpler to just do the full bump test and physically see what actually happens rather than rely on measuring and calculating and hoping you covered all the variables. This becomes more relevant as you change more bits and pieces.
 

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Is there something that I'm missing with that way of thinking?
my above response was only an educated guess based on shocks alone. definitely do not follow my suggestions blindly.

you still need to pull the springs out and push your axle to full bump and determine the actual bumpstop extension requirements for yourself. report back with pictures and exactly how much bumpstop extension you end up using....

still confused? read this: http://www.jeepforum.com/forum/f96/jk-lift-install-suspension-lessons-learned-1513528/
 

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I will be pulling the springs and pushing the axle up to check. I ordered 3" bump stops from Performance Accessories and will cut them down if necessary. What I'm hoping is that I don't need MORE than 3".

My question was strictly based on perch distance vs. shock travel, I'm ignoring fender-tire and track bar clearance for right now but I will check that as well.

With the tires on the ground so the suspension is at ride height, if I have 9" of space between my spring perches but only 5" of space for my shock to compress before its totally bottomed out, doesn't that mean I need at least 4" of bump stop to avoid damaging the shock or shock mount? That was the question, and I will confirm by lifting the axle to see but I would expect it to be somewhat in line with that.
 

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Oh and one question: do you lift the axle from the center so it goes up evenly on both sides, or lift one corner at a time to get the axle on as much of an angle as possible? Or do you need to do it both ways to confirm any possible clearance issues?

Also, I'm not going to be removing my rear track bar. It took about 5 hours to get that effing thing in, so I will just keep it in place and watch for clearance issues. I assume that should be fine.

I will remove my front quick discos but will leave the rears in place since that should replicate any situation I may be using in the real world in the future.
 

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I do one corner at a time to get optimal arc travel.
 

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With the tires on the ground so the suspension is at ride height, if I have 9" of space between my spring perches but only 5" of space for my shock to compress before its totally bottomed out, doesn't that mean I need at least 4" of bump stop to avoid damaging the shock or shock mount? That was the question, and I will confirm by lifting the axle to see but I would expect it to be somewhat in line with that.
anything is possible - you'll work those details out in your full bump check.

post an annotated picture showing where exactly you are measuring from...maybe your measuring is a little off.

read the link i posted above. it steps through the procedure of how to install a lift and check all this stuff in one shot. its on a JK, but everything is still the same on a TJ (or any other coil sprung solid axle vehicle for that matter).

Oh and one question: do you lift the axle from the center so it goes up evenly on both sides, or lift one corner at a time to get the axle on as much of an angle as possible? Or do you need to do it both ways to confirm any possible clearance issues?
you can push up from the center with one jack to check full bump, or use two jacks on both sides to. two jacks is easiest because you can check full bump, full droop, and full flex on both sides in a matter of minutes.

if you're using one jack you need to move it to each side to check full flex. full flex is one side totally drooped, one side totally stuffed.

you need to check both. full flex is most useful for checking tire clearances. full bump is most useful for checking suspension clearances. full droop is good for checking brackets for interferences and brake line length.

with the shock lengths you're installing you will definitely need longer brake lines.

Also, I'm not going to be removing my rear track bar. It took about 5 hours to get that effing thing in, so I will just keep it in place and watch for clearance issues. I assume that should be fine.
the track bar will probably bind up and likely won't allow the axle through the whole cycle, you may have to have a buddy bounce on the downward side when checking full flex. are you using the stock track bar with a relocation bracket, or what? that is very likely the reason it took so long to get in (binding) - or you're just simply doing it the hard way. i'd suggest doing your full bump check with and without the track bar in the rear, because you may find the track bar to be your limiting factor (watch for hitting on the frame at the gas tank mount). If you find that to be the case, you may need to change it out for better clearance. also pay attention to the relocation bracket vs fuel lines. they often hit the fuel lines at bump.

I will remove my front quick discos but will leave the rears in place since that should replicate any situation I may be using in the real world in the future.
with the shock length you're installing, you'll find the factory rear sway bar links will bind up. you will have to disconnect them to accurately cycle the axle - then you'll need to buy/install/make longer length rear sway bar links. if you already have links of the appropriate length installed, i'd still suggest unhooking them - it's only two bolts and less than a minute.

also make sure you loosen the control arm/track bar bolts if you're using ends that have bushings. don't remove the bolts - just loosen, so the sleeve can rotate with the bushing. if you've got flex joints you can skip that step because they will rotate freely on their own.
 

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Thanks for the info...

Complete parts list:
Currie 4" springs (lifted front 4", rear 5"... need to address this still unfortunately)
Rancho 255 and 256 Shocks for 4" lift (seem long for this though)
Rubicon Express Superflex adjustable upper and fixed lower control arms
Rubicon Express Front Adjustable Track Bar
Rubicon Express Rear Track Bar Bracket
Rubicon Express front and rear sway bar links for 4" lift
YJ longer front brake lines

Getting the springs out was a bit of a battle tonight but they're out. Not sure whats limiting the droop in the front, I'm guessing the steering linkage which I wasn't able to detach. The sway bar links and shocks are disconnected as well as the RE adjustable front track bar. Using spring compressors we really had to fight to get the front springs out, I know they're pretty long but it sucked. No way I'd be able to get them in over a fixed 4" bump stop, but I figure I can just loosely insert the bump stop inside the spring and once the spring is on the perch then I can bolt the bump stop down to fix it in place.

The rear was easier to get out, the passenger spring just came loose on its own after detaching sway bar links and shocks, the drivers side was limited by the track bar but I used a spring compressor to get it out and after a small battle it was free.

After flexing the axle up evenly on both sides and then individually on either side I found I need 4" of bump stop in the front and 3.75" in the rear to limit travel before any issues.

The 4" front is JUST enough to keep the shock from bottoming out, but it also keeps the RE adjustable track bar from hitting the front diff, by just a couple mm.
The 3.75" rear is JUST enough to keep the shock from bottoming out, and it also is almost where the stock rear track bar on RE track bar bracket would make contact with the body. It does push up the fuel lines a bit as is but they see to have some free movement so that seems ok.

I expected to need the 4" of bump stop because of the longer shocks, but I'm surprised that it is required for the track bars... lots of people run those and many just run 2" of bump stop, makes me wonder if many people aren't truly using enough bump stop.

So after finding what I did:
1) my measurements without doing any of this were very close to being on point (measuring distance between factory solid bump stops, minus the distance your shock can travel before fully compressing).
2) I don't know where the numbers suggested here come in to play, they seem quite a bit short and could lead to a number of issues.

Now the question is, how can I run a 4" bump stop? I ordered 3" body lift pucks (3" diameter front, 2" diameter rear but I'm going to need more than that.
I have left over hockey pucks I can run in the front by stacking four 1" pucks on top of each other and bolting down to the bottom. For the rear I have a 3" bump stop on the way to bolt to the top, but I'm wondering if I can bolt one hockey puck to the bottom of the spring perch to get me to the proper bump stop extension length.

If anyone else has ideas on how to add 4" of bump stop to both front and rear please let me know, I'll be doing some research in the meantime!
 

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My lift is very similar to what you have and I also run 4 inches of bump stop through a combination of longer upper and lower bump stops. It still flexes like mad and fully stuffs my 35s into the fenders.
One thing you will want to do is to grind the lip off the front upper bump stop cup as it will hang up on your springs at full droop and make an annoying twang as the spring move past it.
Sorry but I'm out of town so I can't go look at my jeep, but I believe I have 1 inch longer upper bump stops and a hockey puck under the RE 2 inch lower bp stops up front.
I believe in the rear, all my bump stops are upper extensions that also were designed as body lift spacers.
 

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If anyone else has ideas on how to add 4" of bump stop to both front and rear please let me know, I'll be doing some research in the meantime!
I bought 3", and 2" 6160 aluminum round bar stock for mine. I looked at their scrap first but they didn't have anything I wanted. I got a 6" piece of the 3" diameter and an 8" piece of the 2" diameter. Cost was ~$35.

I plan to cut it with a portable band saw, surface with a sander to get the face squared and smooth as/if needed, and drill a hole through the center with a countersink for the type of fastener I'm using.
 

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So after finding what I did:
1) my measurements without doing any of this were very close to being on point (measuring distance between factory solid bump stops, minus the distance your shock can travel before fully compressing).
2) I don't know where the numbers suggested here come in to play, they seem quite a bit short and could lead to a number of issues.
Did you take any pictures? Posting pictures is kinda the point of this thread!

Maybe we can provide suggestions to help you out. 4" of bump with 4" of lift is way too much IMHO... Maybe you have the wrong shocks, maybe you need different track bars, maybe you can do something simple...who knows. But we can't see what you're looking at, so its really hard to guess randomly. My magic crystal ball is broken :rofl:

And yes, you can very well run into issues if you blindly follow the suggestions in this thread. The numbers here are just estimates that I've put together, they are by no means an end-all-be-all, and they can not be taken as such. That's why I continuously tell people to push their junk to full bump so they can find out whats going on for themselves.

Now the question is, how can I run a 4" bump stop? I ordered 3" body lift pucks (3" diameter front, 2" diameter rear but I'm going to need more than that.

I have left over hockey pucks I can run in the front by stacking four 1" pucks on top of each other and bolting down to the bottom. For the rear I have a 3" bump stop on the way to bolt to the top, but I'm wondering if I can bolt one hockey puck to the bottom of the spring perch to get me to the proper bump stop extension length.
don't bolt that much hockey pucks down. you can simply order more body lift pucks, or stick one hockey puck in front on each side under the body lift puck.
 

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Front Drivers side with 4" of bump stop mocked up


Front Passengers side with 4" of bump stop mocked up
[/URL]

RE front track bar to diff clearance was almost nil at the 4" of bump stop, so the shocks aren't even limiting my up travel here, seems anyone with an RE trackbar would need 4" of bump stop but their kits only include 2" I believe... hmmm.


Rear Drivers side with 4" of bump stop mocked up (you can't see bout about 1/2 travel left on shock, but the track bar was starting to bind with the underside of the Jeep at this point when the axle was lifted evenly (I think this is called full bump).
http://i324.photobucket.com/albums/...C-0A7B-43C9-AC7E-F228FFDBF06D_zpsglk2zyev.jpg

Flexing the front with swaybar links disconnected... I think I measured 12.5" from perch to perch on the drooped side (and 4" on the compressed side) up front.
Also tested the rear and had 12" of flex with the rear sway links disconnected, but only 7.5" with the sway link connected (again 4" on the compressed side).




This was before I started taking the front spring out, sway link disconnected, don't remember if the shock was disconnected at this point


Getting the front springs out was VERY difficult. Disconnected the track bar, shocks, and sway links. Tried disconnecting the pitman arm but no luck there. Also tried disconnecting the driveshaft but it seemed like it was pushing into the diff so I couldn't separate them. No idea why. With what I did have disconnected, any guesses on what the next limiting factor would be? Or any different technique I should use to get the springs back in? We spent a LONG time going back and forth struggling to barely get them out.
 

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I had 2 jacks so I was able to lift each side to full stuff and check clearance and then raise both sides together, so I think I'm in pretty good shape verifying clearance all around.

What do you suggest to attain 4" of bump stop extension? Here is what I can do:

Front: 1" of hockey puck plus 3" of BB03 body lift spacer all bolted to the bottom (does it matter which goes on top and which goes on the bottom?)
Rear: 3" of MB03 body lift spacer bolted to the top plus 1" of hockey puck bolted to the bottom (Not sure if the hockey puck fit nicely in the bottom of the rear because the spring does taper at the top and bottom, may need something smaller in diameter)

I'm not sure if that setup will work but its what I have currently and what I was thinking may solve this. I'm trying to find other people who are running 4" of bump stop to find out what they're doing but haven't seen much. I do know that some people run a replacement for the stock jounce bumper in the top but none of those say how much they actually extend the effective bump stop.

edit: Just remembered I do have a 1" transfer case drop installed as well which is probably the same exact style as the pieces I just ordered to use as these bump stops. I could steal 2 of those to use in the rear if that is a better solution. (I'd replace those two pieces with hockey pucks temporarily for the tc drop--which is coming out soon for a sye and cv driveshaft anyway).
 

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Won't let me edit my post, one picture didn't show up so I'm reposting it here:

Rear Drivers side with 4" of bump stop mocked up (you can't see bout about 1/2 travel left on shock, but the track bar was starting to bind with the underside of the Jeep at this point when the axle was lifted evenly (I think this is called full bump).

 

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Won't let me edit my post, one picture didn't show up so I'm reposting it here:

Rear Drivers side with 4" of bump stop mocked up (you can't see bout about 1/2 travel left on shock, but the track bar was starting to bind with the underside of the Jeep at this point when the axle was lifted evenly (I think this is called full bump).
wow, thats way more bump than I expected you would need. Have you measured the shocks to verify the compressed lengths they advertised? The shock bodies look too large. And have you verified the PN's are accurate? Because 16" compressed length should not need 4" of bump. You may have the wrong shocks? Mislabeled, wrong stuff delivered, or whatever.

Also, I'd definitely ditch the RE track bars, both front and rear....Currie or Metalcloak will help you clear much better.

Additionally, the bumpstop pads are not lining up at full bump in front because the uppers are way too long - and this is contributing to your bad clearance. I would suggest hacking some length off the RE uppers - IIRC they only adjust to 15.5" or something, which is 1/2" longer than stock. This thread has more detailed info from mudb8. If you can pull the front axle back more in the wheelwell, with 14.75-15" uppers and 16-16.375" lowers, you may get better clearance on the diff cover. You will likely need cam bolts on the lowers since yours are fixed length. This is going to help with your alignment/caster & axle position a lot too.

Yea, funny how RE includes 2" bump, huh? Somebody at RE did their homework, eh? That's why you have to check/verify this stuff for yourself.

The driveshaft should not be pushed into the diff like you mentioned. Here's the deal - when the axle droops, the driveshaft is COMPRESSED because the control arm arc makes the wheelbase get shorter. Opposite is true - at bump, the driveshaft extends because the wheelbase gets longer. If your driveshaft is bound up, and you can't remove the diff side at full droop then you need to have your driveshaft SHORTENED, or you need to limit your down travel so the shaft doesn't bottom out. You also should check the rear for the same problems (you should have a SYE/CV shaft at 4" of lift).

Now, in the rear, you need to SHORTEN the lower control arms and lengthen the upper arms when you correct pinion angle for the CV shaft. IIRC, RE fixed lowers are all 16", which does not work in the rear. You actually want stock length (15.75") and less. Notice how your rear bumpstops don't line up? That's because the axle is pushed too far back in the wheelwell. The bumps should line up better at full bump. So you'll need to get new lowers in the rear that will allow you to adjust shorter than stock. Savvy or Currie are the only ones I know of that do.

OK, to wrap up: Check on the shock PN's and see if they are correct. Do the track bars & control arms corrections mentioned. If those are the shocks you're going to run with, let's talk further about how to get you more reasonable uptravel by cutting shock mounts off and relocating them.
 
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