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View Full Version : Anyone have another solution for extending bump stops?


tomp
07-10-2007, 04:26 AM
Would like to hear all the solutions you guys (& Bebe) can come up with to extend the front factory bump stops?

Worst case, I can try the Daystar stops that are suppose to slide over the shock, but I am afraid I will run into issues being that the H3 shock has that big bracket on the end the Daystars are suppose to slide over.

Any ideas are appreciated. thx

HummBebe
07-10-2007, 05:21 AM
What thread was that in again?

H3slate
07-10-2007, 05:28 AM
Here is some information I found about Light Racing jounce shocks which would replace our oem bump stops.

With any suspension system, there are four positions in the range of movement. The first is the compression stage. As the vehicle encounters a variation in terrain, the compression cycle begins. As the energy is absorbed by the springs and shocks, the axlehousing-or A-arm, in the case of IFS-moves upward until it reaches the second position in the cycle: the point of maximum compression, or the "bump" position. At full compression, your vehicle's suspension can no longer dampen the energy of a bump. Most vehicles are equipped with rubber bumpstops, which act as last resorts to lessen the impact between the suspension and chassis during the bump stage. In most cases, OEM bumpstops do a decent job. However, when excess compression occurs, the energy travels right through the rubber block and continues through the chassis. This is the part you feel in your back and typically followed by an expletive.
Following the compression stage is the third position, called rebound. This is what the suspension must do to dissipate the energy absorbed during compression. The rebound energy correlates directly to the energy of the compression and is again controlled by the shocks. The more energy that is stored in the spring during the compression stage, the more energy must be relieved by the rebound stage. If the shocks fail to dissipate all the energy contained during the rebound cycle, the excess energy tries to force the wheels downward, often causing the vehicle to bounce off the ground. This is not a good thing because when tires leave the ground, control is lost.
This leads us to the final stage of the cycle: droop, which is the opposite of bump. At full droop, the suspension is extended as far as it can go. Typically, the shocks or springs dictate the position of full droop. During a high-energy event, the excess force exerted at full droop can be noticeable and is properly characterized as "topping out."
How Jounce Shocks Work
The Jounce Shocks begin working during compression. As a fixed-containment air spring, the Jounce Shock can convert a tremendous amount of mechanical energy into heat. The effect is virtually transparent until the suspension system reaches the 3/4-compression mark. At this point, you would normally raise your shoulders and squint in anticipation of a hard bottoming-out, but instead the Jounce Shock piston compresses a cavity of nitrogen and quickly transforms the would-be violent energy into heat, thus reducing the harshness of the impact. The graph below illustrates these forces with and without the Jounce Shocks installed.
pulled from here: http://www.fourwheeler.com/techarticles/suspension/129_0601_2005_gmc_duramax_jounce_shocks/index.html

Jounce shocks can be found here:

http://www.lightracing.com/lightracing25870.html

Expensive, for front and rear jounce shocks 1495.00
Front jounce shocks can be had for 725.00

These shocks have to be welded to the frame, so not a diy for everyone.

HummBebe
07-10-2007, 06:12 AM
What about something like this???

http://www.timbren.com/aeon-rubber-springs.htm

found here: http://www.pirate4x4.com/forum/showthread.php?t=347598&highlight=bump+stops

H3slate
07-10-2007, 06:50 AM
Not as pretty as the jounce shocks, :)

but they look like they would get the job done. The price is right Bob!

Sewie
07-10-2007, 07:24 AM
What about something like this???

http://www.timbren.com/aeon-rubber-springs.htm



I thought I saw those mentioned on another thread here, also. Someone just needs to figure out the right size.

Stevenblanca
07-10-2007, 02:20 PM
You just need to find the proper load and length of a double convolution Timbren. length wise 4 TB turns = 2.5 inch, 8X TB turns = 3 inch,

You need a spacer, bolt and nut. The nut will be very difficult to install so I'll use a blind bold instead. I'll post pictures when I have my Bilstein, Timbren, adjustable swaybar setup. I think I'll settle on 6 TB turns. Unless you want to use foam bumpstop I think this is the best cheapest and totally reversable solution.

P.S.

You can find foam bump stops at http://www.powerflex.co.uk/products.asp?cat=0041&catalog=0141
but the load it can handle is unclear.

tomp
07-10-2007, 09:53 PM
On my H2, I used stock length shocks and shock extensions. This made it a necessity for me to extend my bump stops as I would now bottom out on the shocks harder than I would had the bump stops still been there to slow/stop the motion.

However, since I used shock extensions I was able to get away with using a spacer between my OEM bump stop & mount. Here is what I made to take up the 1/2" space between the control arm and bump stop:

tomp
07-10-2007, 10:01 PM
On the H3, I used the longer Cognito shocks. This allows me to "bottom" all the way down to where it did from the factory. However, the bump stops are not touching as they did from the factory. This causes me to have more body roll, nose diving when braking and getting blown around by side winds on the highway.

Can anyone confirm if the factory stops are pressed in or held in by a screw or bolt? They appear to be pressed-in, but there is also a hole in the center that may have a screw/bolt through the hole.

It may be possible to make a spacer similar to what I did on the H2 and run a longer bolt through the spacer into the frame or bump stop mount.

fourfourto
07-10-2007, 10:08 PM
:popcorn: wouldnt a hockey puc work,it should take the abuse http://www.elcovaforums.com/forums/images/icons/icon5.gif

tomp
07-10-2007, 10:23 PM
:popcorn: wouldnt a hockey puc work,it should take the abuse http://www.elcovaforums.com/forums/images/icons/icon5.gif

Hockey puck + little duct tape = life is good:twak:

H3slate
07-11-2007, 01:55 AM
Can anyone confirm if the factory stops are pressed in or held in by a screw or bolt? They appear to be pressed-in, but there is also a hole in the center that may have a screw/bolt through the hole.

It may be possible to make a spacer similar to what I did on the H2 and run a longer bolt through the spacer into the frame or bump stop mount.

The oem bump stops are pressed in.

tomp
07-11-2007, 03:21 AM
Yep, I just pulled one out & there is no bolt or screw in there

Casey
07-11-2007, 09:36 PM
I haven't looked but is there a hole in the top of the mount? If there is, a ball joint press or similar could be used to press the oem one out from the top if there is clearance. Anyone have access to a factory service manual? There should be a procedure in there for changing the OEM ones out. Once you get the lower a-arm out, and the bump stop out of the hole, seems like that location could be very easily modified to fit either a spacer or an aftermarket bump stop. With the variability in construction and materials, you could probably even do some on road suspension tuning by choice of bump stop rate.