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Can you find smaller bumpstops for the front?

backcountryislife

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858
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Dumont, CO
noticing on bigger features I run on the bumpstops, wondering if I could get a smaller one, and get more uptravel?

Getting more droop without the sway bar, but seems like if I got rid of the bumper I could go as far up as I do down?

Any ideas?


I see lots of folks add BIGGER bumpstops when they lift... can't imagine why you would want that off road?
 

06 H3

a.k.a. "The Jackal"
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9,505
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Meridian, ID
For on road use I can see it causing a lot of sway and extreme leaning in corners, so for a daily driver that would suck but seeing yours isnt I dont see why not. Just remember you dont want to go too far up as you could damage the steering rack as it puts force downward if you push the limits on uptravel. I would cut off some and reinsert it and go from there. You could always get rid of more if you want more up travel.
 

davidh3

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334
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N/A
Better not!

from my experience on the highway without the bump stops(similar to having smaller bump stops), the drive quality was really poor, and the front end slightly bounced all time. especially, when you make a turn on highway, the diving front end will make the handling more difficult.

I can't wait to install new bump stops.
 
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06 H3

a.k.a. "The Jackal"
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9,505
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Meridian, ID
Well you could go the expensive route and use air bumps...recon and Bebe use them IIRC. 4wheeler magazine's project H3 had them also. They used jounce racing bumpstops and then seeing you could adjust them you could get some more uptravel

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backcountryislife

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Messages
858
Location
Dumont, CO
Not too worried about on road handling anymore, this thing likely won't see above 18 psi & connected swaybars again till october. I'm thinking maybe a smart plan would be to buy another set, cut them down, and swap these in for summer use, then put my stock ones in there for winter when we're not wheeling. (Or... cut these down, and buy some extended ones for winter maybe?)


At $400 ish before mounting options, I think the air bumps are out, though that seems like the perfect setup... add air for on road use, and drop psi for wheeling.

Right now the 1/2shaft only goes to horizontal at top out... I'd have to go a ways before I had any real issues with there being too much up travel I'd think?
 
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elripster

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Messages
111
Location
San Diego
Interesting question. I would shy away from that. The jounce bumper in our trucks is an integral part of the suspension. Reducing it will not only have the on-road ride issues mentioned will reduce the hit the suspension can take before something bends. You posted a picture showing the stop pretty well mashed. Not sure how much farther you can go before metal contacts metal but probably not much. It might make an improvement that's worth that tradeoffs others have mentioned and will probably come down to personal preference.

Frank
 

skippy

Well-Known Member
Messages
471
Location
brisbane australia
it will make the ride quite bad it will make the front dip under braking and be very floaty as you will notice they are more of a ride than a bump stop!

it is a lot like cranking the t-bar without the tension
 

elripster

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111
Location
San Diego
Our jounce bumpers are basically variable rate springs as opposed to only suspension travel limiters. I like the design but you do have to really think about modifying them as there will be some larger tradeoffs.

Frank
 

backcountryislife

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Messages
858
Location
Dumont, CO
it will make the ride quite bad it will make the front dip under braking and be very floaty as you will notice they are more of a ride than a bump stop!

it is a lot like cranking the t-bar without the tension



I'm not at all worried about ride quality, I'm worried about keeping my tires on the ground so I don't have to spin & hop to get over things. These are cheap enough that I can go back to stock or otherwise easily when summer is over.

In october, I'll be pulling the locker, and likely swapping these out.... no biggie.


How do you mean though by cranking the T-bar without tension? I don't understand that comment?
 

backcountryislife

Well-Known Member
Messages
858
Location
Dumont, CO
Our jounce bumpers are basically variable rate springs as opposed to only suspension travel limiters. I like the design but you do have to really think about modifying them as there will be some larger tradeoffs.

Frank



From what I've seen when I put a wheel up on a large rock, the control arm hits the bumper... and that's about it. Maybe it's from being cranked too far? (24.25 I think I'm at?) I see a little bit of give... but it seems like 1/4" at most, I'm assuming that they should be giving more than this?


If the problem is torsion bar tension not allowing the bumper to compress, maybe even a smaller bumper might not help?
 

06 H3

a.k.a. "The Jackal"
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9,505
Location
Meridian, ID
I think a lot of people forget that the H3 uses the bumpstops as a part of the suspension. When I was installing my lift in the driveway (over the course of a week) I had a lot of friends stop by with different rigs and they questioned why I installed the bumpstop extensions and said it was limiting uptravel. They dont realize the H3 suspension isnt like a jeep where you just have a bumpstop to prevent the wheel going up into the fender but thats not the case for us. Its being used every time you drive.
 

backcountryislife

Well-Known Member
Messages
858
Location
Dumont, CO
I think a lot of people forget that the H3 uses the bumpstops as a part of the suspension. When I was installing my lift in the driveway (over the course of a week) I had a lot of friends stop by with different rigs and they questioned why I installed the bumpstop extensions and said it was limiting uptravel. They dont realize the H3 suspension isnt like a jeep where you just have a bumpstop to prevent the wheel going up into the fender but thats not the case for us. Its being used every time you drive.

So if that's the case, why does mine stop as soon as it touches the bumper do you think?
 

06 H3

a.k.a. "The Jackal"
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9,505
Location
Meridian, ID
Frank, maybe you can verify here but isn't the bumpstop on a jeep has one purpose to stop the suspension before damage and then ours is two stop the suspension before damage, for example, overextending a suspension part or hitting the fender and help in ride quality?

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elripster

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Messages
111
Location
San Diego
Not quite sure what you are asking (Jeep or Hummer?) but I'll give it a shot. Most vehicles use the bumpstops as the last line of defense against damage. They act as cushions at the limits. The vehicle does not ride on the bumpstop in normal operation. Increasingly though vehicle manufacturers are using these multicellular polyurethane jounce bumpers to not only cushion at limits but to act as part of the spring system. Here the vehicle rides on the springs AND the jounce bumper. The jounce bumper lets the suspension designer vary the spring rates making that rate higher as you go up (not down) and at a higher rate the higher you go up. You will notice your jounce bumper has that necked down section where it compresses easily then when that is absorbed it puts up much more resistance. By the time you mash it the bumper is putting up major resistance. That ramping up of the spring rate effect shaves off the peak of the force thus saving other car parts and your spine from the impact.

On a Hummer this lets the truck utilize a softer torsion bar which unwinds more slowly as the wheel extends. That helps to maintain more pressure on a drooping wheel as it droops up until it leaves the ground. More pressure equals more traction. It's a good design.

When altering this design one has to take into account more than just having rubber at the limit. Cutting it down means you took a spring out of the system which is why everyone reports such a floaty ride when the vehicles are raised via torsion bar adjusting (a-arms no longer in contact with the jounce bumper). Whether or not one finds the trade offs of cutting a jounce bumper worth it is probably up to personal preference but the trade offs are presented here for consideration.

Frank
 

Hunner

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Messages
2,334
Location
Arkansas
By totally removing them you will find out real quick what happens.
A safe way to find out is remove one and jack that side up and see what all will be affected.
At some point the wheel well becomes the limit if the suspension and size of your tires is taken into account if other components don't hit first.
I found that up travel when the suspension maxes out is compensated by lifting the vehicle, the sky is the limit, unless you "tump" over!
I experimented with several lengths by cutting and combining OEM pieces. For me on the 06 and the Alpha 1/2 inch longer seemed to be the acceptable level with moderate cranking to 23 1/2 inch and a winch and brush guard mounted.
I also have different tie rods with more articulation and Bilsteins longer than OEM.
_DSC6976_resize.jpg

Going with shorter like the OP inquired about will be an interesting thread to follow.
 
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backcountryislife

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858
Location
Dumont, CO
I seem to be a ways off the wheel well yet when at full "stuff" up front, I don't THINK it would hit unless I really got rid of the whole thing, and I've got no plan to do that. I just want to be able to get some more realistic travel from the front end on this thing... it's better with the front disconnected, but it's a joke compared to an FJ's articulation. Every little bit counts, just not sure where I'll see other problems.


Not sure how you mean by jacking that side up? I'd have to jack up the wheel though right? So I'd have to lift the wheel about 3'+ in the air to get any kind of useable result... I just don't have the ability to do that. Used to know all sorts of folks with forklifts... can't think of any right now.


I know I don't want a hard "stop"... the design of this thing seems like that wouldn't work well, but I'd think like alrock said in his technical write-up in post 2, "sawzall":), that seems like cutting SOME of it off could do the trick without eliminating the safety factor keeping metal off metal.


Like I said though... on a 3' rock, mine isn't compressing the bumper hardly at all... so I think there's more spring force that's the issue rather than it solely being a bumper issue perhaps.
 

Hunner

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2,334
Location
Arkansas
A floor jack under the A-arm and lift until the suspension maxes out and the whole vehicle starts rising is how I checked all that out. That way you can see how it works and maybe come to your own conclusions.
 

backcountryislife

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Messages
858
Location
Dumont, CO
A floor jack under the A-arm and lift until the suspension maxes out and the whole vehicle starts rising is how I checked all that out. That way you can see how it works and maybe come to your own conclusions.


If I'm not even pushing the bumper when the wheel is on a large obstacle, I can't imagine just pressing the A arm up would max me out? I'd think I'd need to be on a downhill, and then put my wheel on something big, no?

The vehicle would start rising when it's nowhere near maxxed out I'd think.


It just seems like on the trail I can't get that bumper to collapse hardly at all.
 

06 H3

a.k.a. "The Jackal"
Messages
9,505
Location
Meridian, ID
This is somewhat off topic...I missed it before but you said you were cranked at 24 1/4. That's pretty high...that's also a possibility on why you have had steering rack issues, the tie rods max out and then push up on the rack.

Also to this day many people have argued on the more you crank the torsion bars you lose some travel. Idk what's true and what isn't but its been a debate for a while.

Frank, using a higher rate T-bar (alpha torsion bar or SAW t-bars) affects how the suspension reacts for loading and unloading but is the higher rate a good or bad thing?

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backcountryislife

Well-Known Member
Messages
858
Location
Dumont, CO
Not off topic at all... that's exactly what I'm trying to figure out.:cheers:

You guys say the bumper gives... I don't see that on my setup... but maybe it's because I'm cranked too far?

If dropping the crank a bit will allow me more up travel, then I'm all for it. With it disconnected I'm going to get full droop either way, but if that helps me go up a bit, then it's a good thing.
 
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