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Topic Review (Newest First)
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.
03-15-2014 10:31 PM
OhSixTJ 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?
03-14-2014 07:55 AM
UnlimitedLJ04
Quote:
Originally Posted by nicolas-eric View Post
I want a good on road ride. Is 5" uptravel up to the cup enough for that?
once again, this is subjective. depends what you're looking to do.

but so you stop asking the same stuff, i'll just take a wild guess and say yes it'll be fine.

Quote:
Originally Posted by nicolas-eric View Post
With bodylift pucks I canīt use countersunk bolts. With normal bolts the jounce would rub at the bolt head. That would damage the jounce over the time IMO.
Or is that wrong?
it's not really a problem that i've seen. but if you're that worried, countersink it yourself, or use button head bolts.

Quote:
Originally Posted by nicolas-eric View Post
Is the spring perch massive or only thin sheet metal?
it's not massive, but it's thick enough to tap and grab a few threads of a 1/2-13 UNC.

Quote:
Originally Posted by nicolas-eric View Post
Will something like a 3/8" (about 10 mm) bolt be enough?
3" OB body lift pucks will be 1/2" ID. you need to be able to grab the shoulders of the pucks to bolt them on.

Quote:
Originally Posted by nicolas-eric View Post
How long should these bolts be?
BS length + ?" ?
long enough to hold the puck down. use a tape measure.
03-14-2014 05:38 AM
nicolas-eric
Quote:
Originally Posted by UnlimitedLJ04 View Post
again...its kinda subjective....depends what travel ratio you're looking for.
I want a good on road ride. Is 5" uptravel up to the cup enough for that?
I do only slow offroading without any fast tracks.

Quote:
Originally Posted by UnlimitedLJ04 View Post
just use body lift pucks....
With bodylift pucks I canīt use countersunk bolts. With normal bolts the jounce would rub at the bolt head. That would damage the jounce over the time IMO.
Or is that wrong?


BTW I just ordered the RS9000XL shocks.
In 1-2 weeks they will be here.
When I install them Iīll also install the aditional BS extensions on the spring perch. For that I have to remove the springs and can measure the needed BS length like you said in this thread.

Is the spring perch massive or only thin sheet metal?
Will something like a 3/8" (about 10 mm) bolt be enough?
How long should these bolts be?
BS length + ?" ?

Thanks for all your answers, that makes these things way easier...
03-13-2014 04:06 PM
UnlimitedLJ04
Quote:
Originally Posted by nicolas-eric View Post
That means +5" uptravel to the cup (not the jounce) will be ok?
again...its kinda subjective....depends what travel ratio you're looking for.

Quote:
Originally Posted by nicolas-eric View Post
Iīm already thinking about cutting the rear spring perches and welding them back on in the right position. But that would be a problem with our German TUV (Association for Technical Inspection). They donīt like welding on suspension parts.
Itīs the same problem with new shock mounts.
if you do it well, they won't even notice you did anything, unless they are experts in TJs. and you build plenty of justification around how it's safer in the correct position vs the poor position with a lift.

Quote:
Originally Posted by nicolas-eric View Post
Is it a good way to extend the BS by bolting hockey pucks to the spring perch?
just use body lift pucks....

Quote:
Originally Posted by Digger84 View Post
If I was going to turn a couple custom length bump stop extensions out on the lathe which is better scrap stock to use 2 inch aluminum rod or 2" derlin rod

Would either last as well
both will be just fine for the rear (2"). for the front you want 3" OD. since you have a lathe and bar stock, I'd say push to full bump and measure exactly what you need. round up to the nearest 0.3-0.5" and make custom lengths.
03-13-2014 03:45 PM
Digger84 If I was going to turn a couple custom length bump stop extensions out on the lathe which is better scrap stock to use 2 inch aluminum rod or 2" derlin rod

Would either last as well
03-13-2014 02:57 PM
nicolas-eric Ok thanks!

That means +5" uptravel to the cup (not the jounce) will be ok?
Then I would be fine with the RS9000 shocks.

Iīm already thinking about cutting the rear spring perches and welding them back on in the right position. But that would be a problem with our German TUV (Association for Technical Inspection). They donīt like welding on suspension parts.
Itīs the same problem with new shock mounts.

Is it a good way to extend the BS by bolting hockey pucks to the spring perch?
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