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Topic Review (Newest First)
08-09-2014 10:27 PM
UnlimitedLJ04
Quote:
Originally Posted by Oppugnall View Post
Unlimited:

Such as in these threads?
Front
Ford f-150 shock towers up front- Mini write-up - JeepForum.com

Rear
Outboarded rear shocks: Done. - JeepForum.com

Is there a thread or any info that you'd recommend that will help decide what's the maximum travel shock I can then fit taking into account moving shock mounts? What's my next limit given body lift and highline fenders. I'm thinking will be body/fender again at that point.
yes, those are examples of how to relocate/modify the shock mounts to achieve more travel.

after all that your limiting factor will likely be the springs and/or control arms - depending on your travel expectations. If you're unseating the springs, the travel is essentially useless. Also, at some point the control arms & track bar become problematic...short arms tend to "steer" the axle when flexed. You can easily run out of the travel at the front single shear frame end track bar bracket. You also bind the axle side mount, so that needs modified. Similarly, you eventually bind the rear brackets.

Generally, these types of shock modifications are part of a full suspension redesign - custom mid/long arms & brackets to dial in geometry, custom track bars & mounts, axle swaps, aftermarket spring perches, etc. You also need travel limitation on the extended end too - limit straps.

Just doing big travel with stock parts doesn't complete the package. The goal is make this stuff all work together. That discussion is well beyond the scope of this thread, and even this forum. That discussion belongs on pirate, or JF to some degree.
08-09-2014 12:54 PM
Oppugnall Unlimited:

Such as in these threads?
Front
Ford f-150 shock towers up front- Mini write-up - JeepForum.com

Rear
Outboarded rear shocks: Done. - JeepForum.com

Is there a thread or any info that you'd recommend that will help decide what's the maximum travel shock I can then fit taking into account moving shock mounts? What's my next limit given body lift and highline fenders. I'm thinking will be body/fender again at that point.
08-08-2014 10:51 AM
leemastergt
Quote:
Originally Posted by Oppugnall View Post
Given what I've read and what I can understand after reading through this thread twice. I'll have to bumpstop to prevent overtravel in upwards motion to prevent shock damage. Should I then pick a shock that allows for more droop so that I'm keep up my full travel just more of it will be down travel? Or as you state relocate shocks for more uptravel, and is this part of the purpose of many people outboarding their shocks? My research shows that its a bit difficult on the rear axle I run ford 8.8 due to less width.

Thanks for your help, read a couple of your threads definitely help make concepts more understandable.
Probably depends on how you want to wheel and on what terrain. If you're doing a lot of desert racing, you'll want much more up travel than if you were doing strictly rock crawling. Lots of guys who go to longer shocks and change mounts try to get about equal up and down. So that they're a more all-around kind of rig. That's what I did. However, there are also plenty of people who play exclusively in the rocks with only 3-4" of up travel and running 11" or 12" shocks anyway. My research here, on Jeepforum, and on Pirate4x4 didn't give me a clear answer. Not even from Blaine!
08-08-2014 10:40 AM
Oppugnall Given what I've read and what I can understand after reading through this thread twice. I'll have to bumpstop to prevent overtravel in upwards motion to prevent shock damage. Should I then pick a shock that allows for more droop so that I'm keep up my full travel just more of it will be down travel? Or as you state relocate shocks for more uptravel, and is this part of the purpose of many people outboarding their shocks? My research shows that its a bit difficult on the rear axle I run ford 8.8 due to less width.



Thanks for your help, read a couple of your threads definitely help make concepts more understandable.
08-08-2014 06:44 AM
UnlimitedLJ04
Quote:
Originally Posted by Oppugnall View Post
The more I read these posts, the happier it makes me that I'm putting together my own lift. I have 2" BDS coils on order, I skipped their 5500 shocks and buying bilstein 5100 shocks. Is there a way to help decide collapsed shock length? The length based on info in this thread seems 13.5 front and 12.5 rear. Sound about right?
that's close to stock length, and with only a 2" suspension lift that's fine if that's the best lengths you can get from Bilstein. with that low of a lift and those of big of tires you won't get a lot of travel unless you relocate/fabricate your own shock mounts.
08-08-2014 06:36 AM
Oppugnall The more I read these posts, the happier it makes me that I'm putting together my own lift. I have 2" BDS coils on order, I skipped their 5500 shocks and buying bilstein 5100 shocks. Is there a way to help decide collapsed shock length? The length based on info in this thread seems 13.5 front and 12.5 rear. Sound about right?

I have 1.25 JKS BL, 1" brown dog ML, metalcloak fenders, and I'll fitting 35" BFG KM2's.
05-21-2014 12:55 PM
jjvw
Quote:
Originally Posted by retlcd View Post
And to go one step further, the fronts would only need .42 ???? don't think they make them that small. I am really confused with this
Buy the body lift pucks long and shorten them yourself.

Here is what my front looks like.

The puck started out being 3" thick. For my Jeep, I trimmed it down to 1 3/8" on a table saw.
05-21-2014 06:52 AM
UnlimitedLJ04
Quote:
Originally Posted by retlcd View Post
don't think they make them that small. I am really confused with this
who is "they"???

you're making these things. "they" is YOU!
05-20-2014 08:22 PM
retlcd And to go one step further, the fronts would only need .42 ???? don't think they make them that small. I am really confused with this
05-20-2014 08:03 PM
hosejockey61
Quote:
Originally Posted by retlcd View Post
Ok so with this, I just got a 2" BDS SL and it comes with 5500 shocks for a 2" lift. According to their shock specs, the collapsed measurement on the rears is 13.42. So if I take the 13.42 and subtract the 12.25 I get 1.17. So to be safe should I look for 1.25 bump stop extenders for the rear? figuring there is no such thing as a 1.17" one. If the only choices are 1" or 1.5" which is better?
If you have to choose, go with the longer stop. Too short and things will hit.

To get even closer, buy some poly performance body lift pucks and cut them down to your desired size.

With all that said, you can do math but the proof is in the pudding as they say. Cycle your suspension and take your measurements at full bump. Jeeps are not exact from one to the other so your best bet is to just cycle it and then take your measurements.
05-20-2014 07:56 PM
retlcd
Quote:
Originally Posted by UnlimitedLJ04 View Post
For reference:
In front: 13.5" compressed length shocks fit with no bumpstop extension
In Rear: 12.25" compressed length shocks fit with no bumpstop extension

Regardless of lift height - Subtract the compressed length of the new shocks you're trying to fit and you've got a good starting point for the required bumpstop extension.

Example: 15.5" compressed length shock (like OME N66L) = 15.5-13.5 = 2" front bumpstop requirement.

The body lift benefit in regard to bumpstop extension length is that you can run less bumpstop for TIRE SIZE. You still need the same bumpstop extension based on shocks.

Bumpstop extensions are required for four main reasons:
1. Prevent major suspension interferences - like axle housing hitting the oil pan, or track bar hitting a diff cover.
2. Preventing coil bind - prevents damage to springs.
3. Prevent shock damage - prevents shocks from bottoming out.
4. Prevent tire vs steel tub rubbing - prevents damage to the body and tire damage.

Tires are the last on the list because thats the least important job.

If you add a 1" BL, you can fit 1" larger tires, provided #1-3 are already satisfied.

Example:
You have 2.5" of lift and have 14.5" compressed length shocks in front using the stock track bar, with 13.5" compressed length shocks in the rear using a track bar relocation bracket. Notice I've said nothing about tire size.

Now, following the above #1-4 list:
1. You don't need any bumpstops in front to clear the stock track bar, but in the rear you need 1.25"-1.5" bumpstop extension to prevent the relocation bracket from hitting the underside of the tub.
2. The front springs are under 20" in extended length, which means they'll fit in the stock spring towers. You'll need some bumpstop extension in the rear since the springs are longer, and the 1.25"-1.5" from #1 should suffice well.
3. The front 14.5" compressed length shocks require at least 1" of front bumpstop extension. The rear 13.5" compressed length shocks require 1.25-1.5" of rear bumpstop extension, which fits well with #1 & #2.
4. Now you know you need 1" front, and 1.25-1.5" rear. You can run a max of 32" tires on this setup. If you add a 1" BL, you can run a max of 33" tires. If you add a 3" BL, you can run a max of 35" tires.

Got it?
Ok so with this, I just got a 2" BDS SL and it comes with 5500 shocks for a 2" lift. According to their shock specs, the collapsed measurement on the rears is 13.42. So if I take the 13.42 and subtract the 12.25 I get 1.17. So to be safe should I look for 1.25 bump stop extenders for the rear? figuring there is no such thing as a 1.17" one. If the only choices are 1" or 1.5" which is better?
04-18-2014 08:33 PM
konadog this is good information.
04-12-2014 08:13 AM
UnlimitedLJ04
Quote:
Originally Posted by nicolas-eric View Post
I have another question..

How much can the springs be compressed?

A friend hast 1.5" BS extensions in the rear and 2" springs with 1.5" spacers.
The spring would be fully compressed before the lower spring perch hits the jounce.
depends on the springs: length, coil diameter, number of turns, etc.

but yes, you are correct in that you can run into a circumstance where the spring is fully compressed before the BS even does its job. That's called coil bind and it's bad...hence I don't like big spacers + springs.

Unfortunately its kind of hard to measure coil bind yourself because you need a press to fully compress the spring in order to measure it. Its easiest to relying on the manufacturer of the spring for this specification.
04-12-2014 06:45 AM
nicolas-eric I have another question..

How much can the springs be compressed?

A friend hast 1.5" BS extensions in the rear and 2" springs with 1.5" spacers.
The spring would be fully compressed before the lower spring perch hits the jounce.
04-11-2014 01:29 PM
UnlimitedLJ04
Quote:
Originally Posted by _Jeff_ View Post
Rock stars both of you. Thanks so much.

I am just going to ask this as a hypothetical, but if the OME needs, at minimum 1.25" of BSE in the rear, does moving up to 2" create a negative issue? I know someone mentioned earlier that its better to have too much as opposed not enough, but just wondering if too much becomes a problem.
the negative effect is you lose 0.75" uptravel.

the primary reason you install a lift is to gain suspension travel. Why would you want to install a 2" lift, then install 2" BSE's to put you right back to stock travel?

but keep in mind, that's only considering shocks. you've still got to investigate other interferences issues, like tire size and other suspension components.
04-11-2014 12:39 PM
_Jeff_ Rock stars both of you. Thanks so much.

I am just going to ask this as a hypothetical, but if the OME needs, at minimum 1.25" of BSE in the rear, does moving up to 2" create a negative issue? I know someone mentioned earlier that its better to have too much as opposed not enough, but just wondering if too much becomes a problem.
04-11-2014 10:01 AM
nicolas-eric Thanks!
04-11-2014 09:49 AM
UnlimitedLJ04
Quote:
Originally Posted by nicolas-eric View Post
N66: 13.2" to 22.4"
N67: 13.3"to 22.1"

In the front you donīt need BS extensions.
In the rear you need 1.25" BS extension.

The OME 2.5" lift kits come with 0.8" rear and no front BS extensions.
fixed it for you.

the OME kit includes 20mm (0.8") rear BS extensions...not quite enough when you push things to full bump. not only do you need 1.25" to keep the shocks from bottoming out, but you also need the 1.25" to keep the rear track bar relocation bracket from hitting the underside of the tub.
04-11-2014 09:34 AM
nicolas-eric N66: 13.2" to 22.4"
N67: 13.3"to 22.1"

In the front you donīt need BS extensions.
In the rear you need 1" BS extension.

The OME 2.5" lift kits come with 1" rear and no front BS extensions.
04-11-2014 08:08 AM
_Jeff_ It appears this thread has gone the way of the snakes in Ireland and disappeared.

UnlimitedLJ04, thank you for the silly amount of knowledge you have shared, this has been slightly easier to understand than Mud's giant thread on the other site. That one just gives me a headache.
Also does anyone have the measurements for OME 2.5" lift shocks, N66 & N67? I have looked and either missed it or something.
Thanks.

Jeff
03-17-2014 06:19 PM
PO1CJack nothin wrong with being a jeep nerd lol
03-17-2014 02:55 PM
hosejockey61 ^^^^^ Jeep Nerd

03-17-2014 12:47 PM
UnlimitedLJ04
Quote:
Originally Posted by OhSixTJ View Post
Is the tap size mentioned earlier the same size as the bolts that hold the rear jounce cups on?

Or are they a different size?
different.

rear bumpstops are held to the frame by M10x1.5. front spring perch can be tapped with 1/2-13
03-17-2014 12:41 PM
OhSixTJ Is the tap size mentioned earlier the same size as the bolts that hold the rear jounce cups on?

Or are they a different size?
03-16-2014 10:09 AM
OhSixTJ Thanks! Saved me $20!
03-16-2014 09:36 AM
jjvw 2x3" pucks
http://www.amazon.com/gp/product/B00...?ie=UTF8&psc=1

3x3" pucks
http://www.amazon.com/gp/product/B00...?ie=UTF8&psc=1
03-16-2014 08:38 AM
OhSixTJ
Quote:
Originally Posted by UnlimitedLJ04 View Post
Exactly. I'm sure this has been stated many times already in this thread. "Big Blocks" are 3" OD, and work for the front - bolted down to the spring perch. "Mini Blocks" are 2" OD, and work for the rear upper side - bolted to the frame side.
I appreciate the info.

And if I'm splitting the rear between upper and lower spots, I assume "big blocks" for the lower pad?
03-16-2014 07:06 AM
UnlimitedLJ04
Quote:
Originally Posted by hosejockey61 View Post
Just buy performance accessories body lift pucks at the right size or buy larger and cut them down with a chop saw. I just bought a few of the 2 and 3 inch pucks and used the 2" on the front and cut the 3" down to whatever it was that I needed.

This is WAYYY cheaper than buying commercial bump stops.
Exactly. I'm sure this has been stated many times already in this thread.

"Big Blocks" are 3" OD, and work for the front - bolted down to the spring perch.
"Mini Blocks" are 2" OD, and work for the rear upper side - bolted to the frame side.
03-16-2014 01:13 AM
OhSixTJ
Quote:
Originally Posted by hosejockey61 View Post
Just buy performance accessories body lift pucks at the right size or buy larger and cut them down with a chop saw. I just bought a few of the 2 and 3 inch pucks and used the 2" on the front and cut the 3" down to whatever it was that I needed. This is WAYYY cheaper than buying commercial bump stops.
Cool, I'll look into them. Thanks.
03-15-2014 10:38 PM
hosejockey61
Quote:
Originally Posted by OhSixTJ View Post
Last dumb question from me: where do I get these bump stops? Does anyone have a specific favorite or will any of the ones I find in a google search work just fine?
Just buy performance accessories body lift pucks at the right size or buy larger and cut them down with a chop saw. I just bought a few of the 2 and 3 inch pucks and used the 2" on the front and cut the 3" down to whatever it was that I needed.

This is WAYYY cheaper than buying commercial bump stops.
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