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Unread 02-24-2010, 09:58 AM   #16
mcg311TJ
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Good read so far guys..... Keep the info comming

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Unread 02-24-2010, 12:35 PM   #17
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First, to mudb8,and others that have contributed to this and many other posts, I just want to say thanks for all the info you've provided.

Also, just a heads-up for anyone running the RC 2.5" lift with the 2.2 shocks and trying to figure bumpstop extension length. If you remove the rubber bumpers from the shocks (for which I see no value}, the rear shocks compress fully into the shock body, but the front shocks do not. Fully compressed, the fronts still have 1/2" of shaft exposed. So when you measure, you need to add at least 1/2" to the amount of extension required.

For example, I have 4 1/2" of shaft exposed at ride height in the front, so I added extensions to limit it to 4" of up-travel to the cup. As it was stated before, the jounce bumper will fully compress on a hard bump at speed so you need to ignore that when measuring.

I'm sure every shock is different, so be sure to check how much actual up travel you really have. My old SJ hydros had 1/2" of shaft exposed in the rear when fully compressed.
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Unread 02-24-2010, 12:50 PM   #18
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Quote:
Originally Posted by MJBinNM View Post
First, to mudb8,and others that have contributed to this and many other posts, I just want to say thanks for all the info you've provided.

Also, just a heads-up for anyone running the RC 2.5" lift with the 2.2 shocks and trying to figure bumpstop extension length. If you remove the rubber bumpers from the shocks (for which I see no value}, the rear shocks compress fully into the shock body, but the front shocks do not. Fully compressed, the fronts still have 1/2" of shaft exposed. So when you measure, you need to add at least 1/2" to the amount of extension required.

For example, I have 4 1/2" of shaft exposed at ride height in the front, so I added extensions to limit it to 4" of up-travel to the cup. As it was stated before, the jounce bumper will fully compress on a hard bump at speed so you need to ignore that when measuring.

I'm sure every shock is different, so be sure to check how much actual up travel you really have. My old SJ hydros had 1/2" of shaft exposed in the rear when fully compressed.
You need to study up on shocks some more. That half inch of exposed shaft is because there is likely a 1/2" thick jounce cushion inside the shock body.

Also, all quality shocks come with some cushion either internally or externally to stop a hard impact and save the shock in case you bottom them out, especially important with race style shocks that don't have isolation at the mounts.
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Unread 02-24-2010, 02:14 PM   #19
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Where do you get the bumpstops from?? I need longer ones and have not really seen that addressed
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Unread 02-24-2010, 03:37 PM   #20
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Quote:
Originally Posted by mrblaine View Post
You need to study up on shocks some more. That half inch of exposed shaft is because there is likely a 1/2" thick jounce cushion inside the shock body.

Also, all quality shocks come with some cushion either internally or externally to stop a hard impact and save the shock in case you bottom them out, especially important with race style shocks that don't have isolation at the mounts.
I understand that, but when you compress the front RC shocks all the way, it definately feels like it is contacting something pretty solid. The rears will compress all the way to the bottom of the "can" with no gap. When looking at other shocks, I have seen them state that they are internally cushioned, but I have found nothing stating that on the RC 2.2 shocks. I think that the rubber bumpers they have on their shocks is their cushion (which is a pretty poor way to acomplish this in my opinion). I would rather account for it in my extensions than take a chance on busting a shock or mount.

As for your second point...we are not talking about the highest quality shock, and definately not a race shock.
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Unread 02-24-2010, 03:46 PM   #21
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Quote:
Originally Posted by noleswin View Post
Where do you get the bumpstops from?? I need longer ones and have not really seen that addressed
Extending your bumpstops can be accomplished many different ways. Usually it's a spacer to go between the factory mount and bumpstop cup, held in place with a longer bolt. RC sells 2" bumpstop extensions for $14 with the bolts. I would not recomend going that long in the front as it can cause your bumpstop cup to interfere with the spring when it's at full droop.

Another way to do it is to drill and tap the center flat part of the spring perch at the bottom and bolt some kind of spacer in place. I did my fronts using a combination of 1/2" spacer on top and bolted a hockey puck to the spring perch. Some kits come with aluminum spacers to bolt in there...
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Unread 02-24-2010, 05:54 PM   #22
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Quote:
Originally Posted by MJBinNM View Post
Extending your bumpstops can be accomplished many different ways. Usually it's a spacer to go between the factory mount and bumpstop cup, held in place with a longer bolt. RC sells 2" bumpstop extensions for $14 with the bolts. I would not recomend going that long in the front as it can cause your bumpstop cup to interfere with the spring when it's at full droop.

Another way to do it is to drill and tap the center flat part of the spring perch at the bottom and bolt some kind of spacer in place. I did my fronts using a combination of 1/2" spacer on top and bolted a hockey puck to the spring perch. Some kits come with aluminum spacers to bolt in there...
Pics of options or yours would be nice.
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Unread 02-24-2010, 06:40 PM   #23
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Here are pics of mine

Front 1/2" spacer on top and hockey puck on bottom:



Rear 1" spacer on top and hockey puck on bottom (couldn't get a good view of the top spacer)


The top spacers in the front were made from cutting one of the RC t-case drop spacers in half and sanding on a belt sander to desired thickness. The top spacers in the rear are 1" extensions left over from the SJ BB I had previously.

The hockey pucks are drilled and counterbored and the spring perches are drilled and tapped for a 5/16" bolt,
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Unread 02-24-2010, 07:02 PM   #24
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Time for the Hockey Puck pic, Mr. Blaine!... I can't find it.
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Unread 02-24-2010, 07:15 PM   #25
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the only bumpstops that should ever be used on the front are axle mounted stops... like a 2" RE1380. the rear can use the cup extension like the RE1385 Rubicon Express... I prefer Currie's CE9122F and CE9122R, but they are more than 2x's the cost of RE Extensions.

IMO hockey pucks are a waste of Time... if the bell slams down on it, it'll crush.
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DIY highline fenders.... 34-37's under 0"-2.5" lifts
shock length, bumpstop extension, tire size chart click here
DIY shock shifters, more uptravel/better ride




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Unread 04-13-2010, 07:37 PM   #26
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im gonna bring this from the dead


Does anyone have the measurements for a rc 2.5" lift shock?
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Unread 04-13-2010, 08:19 PM   #27
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Originally Posted by Unlimited04 View Post
Im a little late on this thread, but wanted to point something out about this pic. The angle and arc of the shock and control-arm is different, and will effect your requirements when the suspension cycles. This example is not accurate. They may or may not need to be equal.

This is pretty straightforward if you measure first and then buy shocks.
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Unread 04-14-2010, 09:04 PM   #28
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Originally Posted by atxzj View Post
Im a little late on this thread, but wanted to point something out about this pic. The angle and arc of the shock and control-arm is different, and will effect your requirements when the suspension cycles. This example is not accurate. They may or may not need to be equal.

This is pretty straightforward if you measure first and then buy shocks.

The Example is as accurate as you can get. If you measure per my Example, you'll have the correct extension.. I cycle the supensions with coils removed and shocks in place. This stuff isn't a recreational or one time gig for me.

they must at least be equal.
with the stock REAR shock locations, the stop requirements grow about a 1/4" per inch of shock length/extension.... a 14.5" collapsed rear shock length needs about 2.75" bumpstop extension If reloacation brackets like RE, currie, Teraflex, and Rough Country are not used, they need more with them,. and a 13.5" rear collapsed length can operate on 1.25" extensions.



if you measure first and buy shocks that match the available uptravel without bumpstop extensions, you'll end up with stock shocks since they are the only shocks available that match the collapsed length you'll need to keep the shocks from bottoming out. if you measure the distance at ride height from top to bottom and get a shock that splits the difference in collapsed and extended length, you end up with a shock length that is still short and requires bumpstop extension no matter what the lift height is.

To get the TJ/LJ to ride and perform well Takes 6" up travel and 6" down travel, Any thing less plain stinks IMO, and more "flex" will unseat coils, the mounts must be outboard or at least have lower rear relocation. Even RC's 3.25" lift (2.5" springs and 3/4" pucks), has 7" of available rear uptravel with stock bumpstops, using the "new" 8.5" travel shocks, they have 5" uptravel at the point the shocks bottom out, which need 2" extensions to save the axle mounts and bar pins from damage. The example in the above Pic is a RC 2.5" lift with the "original" 10" travel shocks. Yes, it's Extreme alright.... extremely to long for the stock bumpstops and the lift height.
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DIY highline fenders.... 34-37's under 0"-2.5" lifts
shock length, bumpstop extension, tire size chart click here
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Unread 04-14-2010, 09:27 PM   #29
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Originally Posted by mudb8 View Post
The Example is as accurate as you can get. If you measure per my Example, you'll have the correct extension.. I cycle the supensions with coils removed and shocks in place. This stuff isn't a recreational or one time gig for me.

they must at least be equal.
with the stock REAR shock locations, the stop requirements grow about a 1/4" per inch of shock length/extension.... a 14.5" collapsed rear shock length needs about 2.75" bumpstop extension If reloacation brackets like RE, currie, Teraflex, and Rough Country are not used, they need more with them,. and a 13.5" rear collapsed length can operate on 1.25" extensions.



if you measure first and buy shocks that match the available uptravel without bumpstop extensions, you'll end up with stock shocks since they are the only shocks available that match the collapsed length you'll need to keep the shocks from bottoming out. if you measure the distance at ride height from top to bottom and get a shock that splits the difference in collapsed and extended length, you end up with a shock length that is still short and requires bumpstop extension no matter what the lift height is.

To get the TJ/LJ to ride and perform well Takes 6" up travel and 6" down travel, Any thing less plain stinks IMO, and more "flex" will unseat coils, the mounts must be outboard or at least have lower rear relocation. Even RC's 3.25" lift (2.5" springs and 3/4" pucks), has 7" of available rear uptravel with stock bumpstops, using the "new" 8.5" travel shocks, they have 5" uptravel at the point the shocks bottom out, which need 2" extensions to save the axle mounts and bar pins from damage. The example in the above Pic is a RC 2.5" lift with the "original" 10" travel shocks. Yes, it's Extreme alright.... extremely to long for the stock bumpstops and the lift height.
arc still effects shock length. Shortarm suspensions operating on a wide arc exacerbate the issue.

What uptravel does a a stock TJ have? I've never measured, mainly because it never mattered. Much like having 4" or 6" uptravel in the end doesn't matter. I haven't seen anyone here bombing through the desert on shortarms.

In reality, its a stock TJ crapshoot and none of this is really all that scientific when you are working with the factory holes. You seem to place an IMHO in most of your theories which also seem to mimic exactly what is currently cobbled together on your jeep.

Start trying some products on your rig that aren't a decade old, and get back to us.
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Unread 04-15-2010, 09:52 PM   #30
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Originally Posted by atxzj View Post
arc still effects shock length. Shortarm suspensions operating on a wide arc exacerbate the issue.

What uptravel does a a stock TJ have? I've never measured, mainly because it never mattered. Much like having 4" or 6" uptravel in the end doesn't matter. I haven't seen anyone here bombing through the desert on shortarms.

In reality, its a stock TJ crapshoot and none of this is really all that scientific when you are working with the factory holes. You seem to place an IMHO in most of your theories which also seem to mimic exactly what is currently cobbled together on your jeep.

Start trying some products on your rig that aren't a decade old, and get back to us.
Since you are pointing fingers... measure first, then tell me I don't know what I'm talking about. I'm sorry you can't get past the rear steer you gave your self with 3" uptravel, 8" downtravel and can't figure out how to compensate for it or adjust the anti squat.

a stock TJ rides like crap, thats a fact compared to mine, not an Opinion and has 4" uptravel after you compress the rubber bumpstop to nothing..

My cobbled together crap spends alot of time over 60mph + through ditches, on dunes and washboard terrain not to mention takes rock gardens way above a crawl due to my decade old short arm, 14" travel suspension. I'd love to see you try to keep up, then drive it like a car in the curves on the way home. 6" of uptravel not only soaks up bumps, it lets the suspension cycle further before lifting the frame on an obstacle.
In the end, my back doesn't hurt and I still have more ballanced and useable flex than the "New" version of "old" crap and I still have Track Bars.

Theres a TJ with LA's sitting next to my Tj right now, anyone care to see which one rides better? You're more than welcome to stop by anytime, I have a kidney belt for you to Put on before we test drive the Long arm...

exactly how does my "cobbled together" jeep have anything to do with this thread anyhow?

Jerry or wheelin, how bout keeping this Know It All Clown from cluttering up the thread with BS.


I wonder what I was doing when I took these pics, besides eliminating a track bar extension that put it into the tub? Theres a 10" travel shock with 5.25" uptravel on the 2.5" lift with a 3/4" bumpstop extensions there... I wonder how that fits? all that arc and the stop nearly lands flat on the pad... hmmm.





or these.... that already have 2" bumpstop extensions with 5.75" available and useable uptravel, yet the 14.5" collapsed shock length has a whopping 2.75" of uptravel, some of which is due to the tera shock shifters. The pinion angle is also jacked up due to a SYE and a Rokmen belly up skid, which tips the mounts down in favor of uptravel.




Tell me again what the angle/arc of the arm has to do measuring bumpstops... I've already checked and checked, and checked and checked again and came up with a simple solution.
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HighLine Hood Jeepers
TJ Adjustable Track bars
DIY highline fenders.... 34-37's under 0"-2.5" lifts
shock length, bumpstop extension, tire size chart click here
DIY shock shifters, more uptravel/better ride




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