torsion bar adjustement

[Ernie Italy]

For anyone who attempt to use the torsion bar for adjust the front height. When you increase the height of h2 using the screw under the body, verify that the tie rods dont touch the front stabilizer bar with the two front wheel on air (with suspension at full lenght). I have modified this and i have damaged the pitman arms. why ?
On OR the front wheel go on air, the tie rods touch the front bar and can not move. when the wheel touch the terrain cannot move!!!!

Another question ...what is the height of your h2 (no lift and no air suspension) measured from the ground and the red dot on the photo?
My height is 101 cm. on driver side and 102-3 cm. on the pass. side.

[PARAGON]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by PhilD:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Ernie Italy:
But it was necessary because the yellow bumper was completely pressed. </div></BLOCKQUOTE>HGW, what size gap should the bump stop have at the front? Reason I ask is that with the Fabtech kit I had about a 2" gap, which seemed awfully big to me, so I put in some thicker bump stops and now have about a 1/2" gap. I now have less brake dive and less sway around corners, although the ride is a little rougher on rough surfaces. The Fabtech bump stops disintergrated while wheeling. </div></BLOCKQUOTE>This is something that has bothered me since day one. I have gone round and round and can't seem to find anyone that truly knows the answers to this and I have tried to get the answer from anyone short of the suspension design team.

The average consensus (which astounds me if this is true) is that they are NOT bump stops. They are an integral part of the suspension. They call them jounce bumpers or something. I went through the parking lot last year and looked at all of the new '04 H2s and roughly half were riding ON the yellow stops and half weren't.

Of course, to eyeball the trucks most had the "rake" but some were not as noticeable. So, I am told that the suspension can "ride" on the jounce bumpers as they act as "end springs" or something along those lines.

One of my yellow bumper has already collasped about 1/4 the top part of it. I now I have my bars adjusted up and I swear it rides much better in the front. (that's only been done a week now, so has nothing to do with my other front end issues).

I would like to hear the "real" answer on the torsion bars/jounce bumpers/adjustments.

[Ernie Italy]

I have made a mistake... yes crancked the torsion...turn around the screw...ok

[Ernie Italy]

Z height is 4.8 inch - 122 mm.
Z height is the n. 4.
But i think that the drawing is wrong !!!
The drawing come from GM !

[HGW]

Phil is right--longer end links.

When you lift the H2 or any IFS, then you need to look at longer sway bar end links. Just go to the Hummer dealer and look at the stock set up for the front sway bar----then just match it with longer links.

[Ernie Italy]

Phil:
The solution of a longer connector is good and is the same idea of my technician... but we increase only 1". But my problem is ... why i have this problem now?
Stock H2 ..no problem...
RD tie rod ... no problem
cranck torsion bar + new edelbrock xtreme travel with res + steering shock rancho = problem..
I dont think that the steering stabilizer have influence.. the torsion bar now is set to standard position... Edelbrock is the guilty ???

[Ernie Italy]

For anyone who attempt to use the torsion bar for adjust the front height. When you increase the height of h2 using the screw under the body, verify that the tie rods dont touch the front stabilizer bar with the two front wheel on air (with suspension at full lenght). I have modified this and i have damaged the pitman arms. why ?
On OR the front wheel go on air, the tie rods touch the front bar and can not move. when the wheel touch the terrain cannot move!!!!

Another question ...what is the height of your h2 (no lift and no air suspension) measured from the ground and the red dot on the photo?
My height is 101 cm. on driver side and 102-3 cm. on the pass. side.

[PARAGON]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by HummersGoneWild:
Paragon:

Very interesting----I thought I knew it all when it comes to suspensions. Both my trucks are gone right now--when they come back, I will look and also call my suspension buddy in CA. </div></BLOCKQUOTE>Well, I made one more phone call and here is how I understand it. It is actually a "supplemental spring," not "end spring" as I said earlier. It helps to make the whole front suspension more progressive but lessens the overall weight while doing so. Other technical terms are "micro cellular urethane" and "zero-weight spring." I guess, because it supposedly offers spring without the added weight from extra metal in heavier torsion bars.

Also, since the torsion bar is a "smaller" one, it offers a softer ride on the road. The torsion bars are "tuned" with the jounce bumpers to provide the smoothest ride, especially when the suspension compresses fully. Changing the bars or stops will change this "tuning" and make the ride different.

As I understand it, this is something commonly used in small cars. I don't really see how it was conceived that this was a good idea for an off-road vehicle. The physics involved with the H2's front end would seem to preclude using this design. And yes, some cars sit on the bumpers when they are at rest and some don't. Many are designed where the frame component is just barely touching the tip of the jounce bumper.

Go figure!

[HGW]

Looks like a lot of positve caster on your set up--could be the angle of the shot?

Who did the front end alignment? Three degrees is plenty in most cases. You may have to much caster?

If you have a lot, your tie rods could touch your sway bars links. Less caster will move the tie rods out from the sway bars--hard to tell from the photo.

[Ernie Italy]

this is the pics. we have now increased the sway bar connectors... but the lower arms (we call trapezio) have a distance from the ground with stock tires of only 26 cm 10.3" and I have crancked all the torsion bar.. A stock h2 have a clearance of 28 cm in this point.. Someone say that is possible that the first owner (but the H2 have only 1000 km when i have buyed) have change the camm on the torsion bar with another with other design ?!?!?

[Ernie Italy]

My problem start when i come to Hummer Italy...parking my car and the people say..you make O-R with lower lift kit ? Hu? my car is lower than about 5 cm respect to the other.. crank the torsion bar and the front is aligned. After I have some problem due to other modify.
Yesterday I have a discussuion with Hummer and they go under the H2 and say me that with a new car the Yellow bumper is on the pass. side touch a little bit and driver side a 1-2mm of air. But yes..there is something strange.

[HGW]

Yes to your exlplanation.

I am looking into how to properly use the stops on lifted trucks for the best handling. Hopefull I will get some answers or spend a lot of time testing my vehicles.

My Yellow Hummer rides like a Cadillac (sp?) but my Black one needs to be "tighter" up front. I may need to adjust with my bump stops to match my Yellow and I am not sure until I get them home.

[Ernie Italy]

i do not have crancked the stabilizer bar (not the torsion). My H2 on the point that i have marked measure 101-3 cm not and i think that is about 2 cm. less than the highest point of the wheel arch. and now is ok.
But if you turn the screw under the body you can lift ... only the body.
I have installed the Rubberduck tie rods. they are great but after i have installed also the edelbrock shock xtreme with reservoir. something have changed something. now if I lift the two front wheels I can not turn the wheels because the inner part of tie rods touch the torsion bar... what is the solution..

Z height ... where I can measure ? and what is the measure ?

[PARAGON]

I am a little confused, granted a little late to the game, but confused nonetheless. I believe you said when the tire is at full droop (tire in the air) is when the tie rod and sway bars hit.

I believe the torsion bar adjustments should have no effect on this since this is a product of the limitation of the suspension, not the pre-load provided by the torsion bar.

It would appear there is the possibility it is the design of those tie rods that is creating the problem. They might not be offering the clearance at full droop that the stock and Fabtech tie rods do.

[HGW]

Phil:

Good point--we "bounce" (as we call it) our new suspensions around for 100-200 miles, then recheck all connections and get the alignment. We also bounce the new suspension around with the NEW tires and wheels going on the vehicle--not the pre lift tires and wheels.

[Ernie Italy]

Is possible that someone have make the hand on torsion bar exagon and placed in another position??

[Ernie Italy]

From dot to ground... and I have 35 installed. But take a look on the side of the tires. The last terminal of lower arm look to the high.. I think that normal are parallel to ground. Ouch why I dont have studied english in my past!!!!!

[HGW]

Paragon:

Very interesting----I thought I knew it all when it comes to suspensions. Both my trucks are gone right now--when they come back, I will look and also call my suspension buddy in CA.

[Ernie Italy]

I have make it without any problem.... the problem are when I have increased the height with torsion bar...but is not at the same height that GM says..and when I have replace the shocks...

[HGW]

Phil:

Even with 2", a longer connector should be considered.

You will get a better, safer ride (better handling) if you implement your solution.

I am an anal fuss pot about correct sway bar position because these beasts are so heavy. Any adjustment that produces correct sway bar position would be helpful. We have modified some kits by using adjustable sway bar end links---in the rear because it means a lot in the rear. Do not want to "get loose" in the rear as they say in NASCAR.

As you know, but others may not know, even a 2" torsion bar adjustment should be followed up by a front end alignment.