PST torsion bars bent...
#989307
05/10/11 05:29 AM
05/10/11 05:29 AM
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Joined: Jan 2003
Posts: 3,031
Erda, UT
67Charger
OP
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OP
master
Joined: Jan 2003
Posts: 3,031
Erda, UT
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Is it normal for there to be ANY bend in the torsion bar? My brand new PST 1.030's have a very slight sway. I have already installed the drivers side and when grabbing the other one to replace the passenger side I removed, I had the inclination to look down the bar. I was expecting perfectly straight, but instead it looks to be "S" shaped, about 1/16" out of perfect. Is this a problem like I think it is? I leave for Silver State in 36 hours.
11.33 @ 118.46 on motor
10.75 @ 125.35 w/ a little spray
Now, high Speed Open Road Racing - Silver State Classic Challenge, Nevada Open Road Challenge, Big Bend Open Road Race
Rocky Mountain Race Week 2020, 2022 2.0, Sick Week 2023
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Re: PST torsion bars bent...
[Re: 67Charger]
#989308
05/10/11 10:16 AM
05/10/11 10:16 AM
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Joined: Jan 2003
Posts: 17,846
S.E. Michigan
ZIPPY
I Live Here
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I Live Here
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Posts: 17,846
S.E. Michigan
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1/16 from perfectly straight is actually quite good for a part like a torsion bar. They just aren't manufactured with a great deal of precision, and don't need to be, because the hex ends allow for a certain amount of misalignment. I have several OEM and MP bars that are slightly off from being completely straight, all work fine. So  ? No worries
Rich H.
Esse Quam Videri
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Re: PST torsion bars bent...
[Re: Rodney]
#989310
05/10/11 11:19 AM
05/10/11 11:19 AM
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Joined: Jan 2003
Posts: 3,031
Erda, UT
67Charger
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OP
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Joined: Jan 2003
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Erda, UT
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EDITED FOR CLARITY
No offset hexes, but there is an "R" and "L" forged into the back of the bar. The OEM .925ish 440 bars that came out had exactly 1/2 flat of rotation, 30°.
Now to be clear, I'm talking about an S bend along the length of the bar, not a twist of one hex to the other... If it's OK, then I'll install it, otherwise today I'm driving 70 miles down to Hotchkis and dropping $400 on a set from them.
Last edited by 67Charger; 05/10/11 11:38 AM.
11.33 @ 118.46 on motor
10.75 @ 125.35 w/ a little spray
Now, high Speed Open Road Racing - Silver State Classic Challenge, Nevada Open Road Challenge, Big Bend Open Road Race
Rocky Mountain Race Week 2020, 2022 2.0, Sick Week 2023
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Re: PST torsion bars bent...
[Re: MR_P_BODY]
#989312
05/10/11 11:36 AM
05/10/11 11:36 AM
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Joined: Jan 2003
Posts: 3,031
Erda, UT
67Charger
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master
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OP
master
Joined: Jan 2003
Posts: 3,031
Erda, UT
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Quote:
Quote:
No offset hexes (exactly 1/2 flat of rotation, 30°) like the OEM .925ish 440 bars that came out, but there is an "R" and "L" forged into the back of the bar.
Now to be clear, I'm talking about an S bend along the length of the bar, not a twist of one hex to the other... If it's OK, then I'll install it, otherwise today I'm driving 70 miles down to Hotchkis and dropping $400 on a set from them.
Yes that S shape is somewhat normal... that occurs
during the pre loading of the bars(the company winds
up the bar to take a pre set so they arent sagging
on the car... that gives you the 30* hex difference)
put them in 
OK, sounds good, but like I said (although somewhat ambiguously), the new bars do NOT have offset hexes. OEM bars thaty came out do, new do not.
Looks like I'll be running them.
11.33 @ 118.46 on motor
10.75 @ 125.35 w/ a little spray
Now, high Speed Open Road Racing - Silver State Classic Challenge, Nevada Open Road Challenge, Big Bend Open Road Race
Rocky Mountain Race Week 2020, 2022 2.0, Sick Week 2023
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Re: PST torsion bars bent...
[Re: 67Charger]
#989313
05/10/11 11:45 AM
05/10/11 11:45 AM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
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Romeo MI
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Quote:
Quote:
Quote:
No offset hexes (exactly 1/2 flat of rotation, 30°) like the OEM .925ish 440 bars that came out, but there is an "R" and "L" forged into the back of the bar.
Now to be clear, I'm talking about an S bend along the length of the bar, not a twist of one hex to the other... If it's OK, then I'll install it, otherwise today I'm driving 70 miles down to Hotchkis and dropping $400 on a set from them.
Yes that S shape is somewhat normal... that occurs
during the pre loading of the bars(the company winds
up the bar to take a pre set so they arent sagging
on the car... that gives you the 30* hex difference)
put them in
OK, sounds good, but like I said (although somewhat ambiguously), the new bars do NOT have offset hexes. OEM bars thaty came out do, new do not.
Looks like I'll be running them.
I'm suprized they dont pre load them... you may find
that the first few months you MIGHT be adjusting the
ride height... the way the bars are heat treated
will give that wavy S but usually its just a minor
sag
EDIT
I would still think they pre-loaded them but just
moved the orientation of the hex when making the bars
otherwise they wouldnt need to have a left and right
Last edited by MR_P_BODY; 05/10/11 11:48 AM.
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Re: PST torsion bars bent...
[Re: MR_P_BODY]
#989314
05/10/11 12:30 PM
05/10/11 12:30 PM
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Joined: Jan 2003
Posts: 3,031
Erda, UT
67Charger
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OP
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Erda, UT
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Thank you for putting my mind at ease. I'm guessing the no-offset is because the spring rate of these bars is about double that of the .920's so there is less preload necessary.
11.33 @ 118.46 on motor
10.75 @ 125.35 w/ a little spray
Now, high Speed Open Road Racing - Silver State Classic Challenge, Nevada Open Road Challenge, Big Bend Open Road Race
Rocky Mountain Race Week 2020, 2022 2.0, Sick Week 2023
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Re: PST torsion bars bent...
[Re: 67Charger]
#989315
05/10/11 01:41 PM
05/10/11 01:41 PM
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Joined: Jan 2003
Posts: 27,468
So Cal
autoxcuda
Too Many Posts
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Too Many Posts
Joined: Jan 2003
Posts: 27,468
So Cal
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At somewhere in the over 1.00" they go to no offset.
My MP .99's have offset. My MP 1.14" don't. I got decent adjustment left in my 1.14" 's.
I haven't starred down at a set of bars to have an opinion about the "S" curve you are seeing.
Last edited by autoxcuda; 05/10/11 02:50 PM.
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Re: PST torsion bars bent...
[Re: 67Charger]
#989316
05/10/11 02:24 PM
05/10/11 02:24 PM
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Joined: Sep 2009
Posts: 203
Sante Fe Springs, CA
Hotchkis
enthusiast
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enthusiast
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Sante Fe Springs, CA
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Quote:
EDITED FOR CLARITY
No offset hexes, but there is an "R" and "L" forged into the back of the bar. The OEM .925ish 440 bars that came out had exactly 1/2 flat of rotation, 30°.
Now to be clear, I'm talking about an S bend along the length of the bar, not a twist of one hex to the other... If it's OK, then I'll install it, otherwise today I'm driving 70 miles down to Hotchkis and dropping $400 on a set from them.
67Charger -
Are you sure the bar is actually curving? Those bars are tapered in the center which might give the appearence of a bend.
We would suggest calling the company from which you purchased the bars. We've never seen a curve in any of the bars we've used (our own or Firm Feel's) so we would suggest you have it checked out.
Just as a bit of Torsion Bar info for the rest of you if you're interested, most of the new high performance bars are not offset like the factory bars. The hexes are identically lined up which is better for lowered cars.
Stock Mopar bars have a 30 degree offset. This offset is what sets up the "preload" and suspension geometry. But that's for a stock spring rate.
Stiffer bars will not twist as much with the load of the car on them, so the ride height and geometry won't be right if they had the same offset. We've seen this problem with 1.16 bars on a challenger, you actually run out of suspension adjustment before the ride height is back down to normal. You need a lot less than the stock 30 degree offset.
Install new bars the way you normally would. The lower control arms will end up lining up with less angle on them. But that won't reduce your physical travel, since the bar will not twist as much under load. The stiffer bars will reduce the effective travel though, they just won't twist as much. So you can actually lower the car more (reducing the physical travel available) since you won't be using that travel.
1.03 bars will give a much more "modern" feel to the handling of your car. New cars run much higher spring rates than our old mopars, which were seriously under sprung in stock form. But it's important to match parts, you'll want to upgrade the shocks to handle the new larger bars.
Hope this helps.
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Re: PST torsion bars bent...
[Re: 67Charger]
#989318
05/11/11 02:27 AM
05/11/11 02:27 AM
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Joined: Apr 2008
Posts: 373
sandwich IL
sublimehemi
enthusiast
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enthusiast
Joined: Apr 2008
Posts: 373
sandwich IL
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received mine the other day,just checked mine and they are perfect.
70 charger ,all aluminum 528 hemi 727 cope rmvb,680hp 670 tq,full sequential holley hp efi,full hotchkis tvs,qa1 k and lowers,borgeson steering box cass viper 11.75 with cass s-trac dana 3.54
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Re: PST torsion bars bent...
[Re: 67Charger]
#989319
05/11/11 02:34 AM
05/11/11 02:34 AM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
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Posts: 52,972
Romeo MI
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Never seen them look like that... I was part of the design team that designed/built the transverse torsion bar set up in the F and M bodies... I did all of the bars for the pre proto's for that design
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Re: PST torsion bars bent...
[Re: MR_P_BODY]
#989320
05/11/11 04:31 AM
05/11/11 04:31 AM
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Joined: Jan 2003
Posts: 3,031
Erda, UT
67Charger
OP
master
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OP
master
Joined: Jan 2003
Posts: 3,031
Erda, UT
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Well, due to lack of time and therefore options, I put them in. My rationale is the fact that a torsion bar is just a straightened out coil spring, or vice versa. The curve is nothing it won't incur during normal suspension cycling. It was NOT, however, how the factory designed them.
Hotchkis,
You guys will be getting my future business. I bought my full set of Bilsteins and a 1 3/8" front sway bar from you at MATS last month, and the fact that you took the time to chime in with some helpful info when PST wouldn't even return my call is a pretty heavy determining factor. Granted, the PST bars were 1/2 the price delivered, but I can see why.
11.33 @ 118.46 on motor
10.75 @ 125.35 w/ a little spray
Now, high Speed Open Road Racing - Silver State Classic Challenge, Nevada Open Road Challenge, Big Bend Open Road Race
Rocky Mountain Race Week 2020, 2022 2.0, Sick Week 2023
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Re: PST torsion bars bent...
[Re: 70blackfish]
#989323
05/13/11 06:57 PM
05/13/11 06:57 PM
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Joined: Apr 2006
Posts: 3,675
Akron, Ohio U.S.A.
roadhazard
master
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master
Joined: Apr 2006
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Akron, Ohio U.S.A.
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Quote:
I would get straight ones, that is not right.
Was putting some bars in my Charger and had to look at them after I saw your post.
My you have little hands and feet 
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Re: PST torsion bars bent...
[Re: roadhazard]
#989324
05/14/11 02:17 AM
05/14/11 02:17 AM
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Joined: Jan 2003
Posts: 3,031
Erda, UT
67Charger
OP
master
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OP
master
Joined: Jan 2003
Posts: 3,031
Erda, UT
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As you can see in my other post, the Charger has been sidelined. I'll try again to contact PST and see what they have to say about them and hopefully get them to either take them back or hand pick me a pair.
11.33 @ 118.46 on motor
10.75 @ 125.35 w/ a little spray
Now, high Speed Open Road Racing - Silver State Classic Challenge, Nevada Open Road Challenge, Big Bend Open Road Race
Rocky Mountain Race Week 2020, 2022 2.0, Sick Week 2023
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