Mopar perf torsion bars ?

[Steverino]

It’s just occurring to me that maybe(?) the body is out of plumb? Just an idea.

This is not impossible, but I'm not certain how the rest of the sheetmetal core support doors and all could fit so well if the body structure was out of spec (rh higher than lh side)


And I'm not certain how I would measure/check the body structure for squareness/plumb that would have this effect on the torsion bars adjustment ?

the rh side sits so nicely with hardly any force/excessive threading in of the adjuster bolt, and the lh bolt needs to go a good 3/4" further in to keep things level

 

[miller]

And I'm not certain how I would measure/check the body structure for squareness/plumb that would have this effect on the torsion bars adjustment ?

It's the front frame, that needs to be checked. Never considered it could be bent.
I check mine, by putting same height jack stands, level floor, the stands at the frame rails behind the front wheel wells. There, the car's frame should be sitting fairly even, side to side. The K member uses four bolts, to fasten it to the frame...measure from each bolt head, to the floor. Your just looking for difference, side to side, not all four being the same, since the car is at an angle. Also measure both front frame rails, forward of the K member, at same locations.
If it's twisted, the measurements will tell you.

 

[Steverino]

It's the front frame, that needs to be checked. Never considered it could be bent.
I check mine, by putting same height jack stands, level floor, the stands at the frame rails behind the front wheel wells. There, the car's frame should be sitting fairly even, side to side. The K member uses four bolts, to fasten it to the frame...measure from each bolt head, to the floor. Your just looking for difference, side to side, not all four being the same, since the car is at an angle. Also measure both front frame rails, forward of the K member, at same locations.
If it's twisted, the measurements will tell you.

Thanks
Will do this tonight, jackstands under the front frame rails but behind the kickup to the wheels, get those even, then measure my k frame bolts distance to the floor, and up near the radiator support as well

 

[Steverino]

It's the front frame, that needs to be checked. Never considered it could be bent.
I check mine, by putting same height jack stands, level floor, the stands at the frame rails behind the front wheel wells. There, the car's frame should be sitting fairly even, side to side. The K member uses four bolts, to fasten it to the frame...measure from each bolt head, to the floor. Your just looking for difference, side to side, not all four being the same, since the car is at an angle. Also measure both front frame rails, forward of the K member, at same locations.
If it's twisted, the measurements will tell you.

I did measure this morning actually

So I'm pretty convinced that we're ok frame-wise everything was less than 1/8" difference between sides, at the k frame attachments, rad support , and also side to side at the rear

I actually set the car on four stands, I still wasn't sure about the effect on side to side lean of the new rear hd leaf springs
I also swapped the rear leaves left and right, just to be certain there was no effect on the front

So then after speaking with the guys at firm feel (who were somewhat helpful) I did swap the bars from left to right as apparently they are the same, and are "point to flat" when laying on flat bench, one end is on flat, the other end is pointed straight up and this has no effect

I have narrowed the issue to the adjuster blade being 3/8-1/2" further up in the control arm with no bolt installed (just pushed up by hand to remove "slack") on the left side vs the right This is the clearance I need to keep the blade from bottoming on the frame rail on hard right turns (this is about the difference between the two blade to frame clearances when car is level at ride height)

So with the new torsion bar crossmember and the lower control arm being possible root causes (because the torsion bar swap between these and .089"'s and also between these .096"'s swapped left to right), I figured maybe control arm ? socket wear ? (pivot bushings are new)

So I borrowed an e body lh control arm, and swapped it in, still the adjuster blade sits 1/2" further up in the control arm BEFORE loading or even installing the bolt, just the freeplay

So I reopened the WTB for the lh lca, perhaps the borrowed one I have has wear also

Also, the hexes are similar in orientation , when flat is at bottom, the bottom of the "finger" is about lined up with the top of the adjuster block window

Maybe I can get a control arm with less wear ?

Or it still could be the new torsion crossmember sockets, but that seems much less likely

Anyway, I may need to retitle this thread or open a new one, because this issue really seems to be about "torsion bar adjuster blade slack/play"

Or I can try to get some feedback from anyone that has torsion bars installed but not "loaded" to see how far up into the control arm , and what the difference is between sides ?

Thanks for any input and ideas.....hopefully I will solve this....this thing needs to be driven !

 

[Wietse]

With the rear anchors being new i do not expect any slack there, but how is the fitment in the LCA's you have been using?
If you slide it in, is there any play or a "tight" fit? (best to try/fit this separate and not under the car)
There are no other ways a LCA can be "worn", most common is that both halves of the arm are getting "spread" which causes axial play on the torsion bar bushing. (this has nothing to do with this issue and can be solved by welding a reinforcement plate on)
You could try loading the bars LH==>RH or RH==>LH and see if it makes a difference, have you been driving it already after adjusting?

In the end i think there is nothing left that could solve this, i also gave up and just set the ride height where i want it to be and enjoy driving the car.

 

[Steverino]

With the rear anchors being new i do not expect any slack there, but how is the fitment in the LCA's you have been using?
If you slide it in, is there any play or a "tight" fit? (best to try/fit this separate and not under the car)
There are no other ways a LCA can be "worn", most common is that both halves of the arm are getting "spread" which causes axial play on the torsion bar bushing. (this has nothing to do with this issue and can be solved by welding a reinforcement plate on)
You could try loading the bars LH==>RH or RH==>LH and see if it makes a difference, have you been driving it already after adjusting?

In the end i think there is nothing left that could solve this, i also gave up and just set the ride height where i want it to be and enjoy driving the car.

I have an angle finder , and am going to try and get more details using it on some flats of each bar to nail down where this "slack" is coming from
The bar to socket fit feels by hand to be similar at all four socket and with all four bar ends, but I need to measure to get more specific

Interesting about the spreading of the lca's, I'm wondering if this can have any effect as the lh bar does slide forward at least 1/4" further in either of the lh lca's , compared to how far in any bar slides into the rh side
I'm planning to swap the lh lca back to my orig one, and while they're both out I can make some comparisons/measurement between the two lh lca's

I did load the bars just to confirm that it did not resolve/change the issue, but I think my difference is already present before even installing the bolts as the lh adjuster blade pushes 1/2" further up into the lca than the rh blade

My understanding of the way the bars are made, (at least the repros) is that while they are "swappable" side to side, they are marked to so that they can stay in the same side/orientation if they are removed later for service as once they've been driven on for a while, they need to stay in their same location

So today I'm going to try and measure some angles and hopefully pinpoint the source of the extra movement/upward travel of the lh adj blade

I'm sure if I can't resolve it, I can set everything ride height) where it was, drive it for now, and I'm sure after a few hard turns/big dips, my adjuster blade will make a few "clearance dents" in the bottom of the lh frame rail...although I'd much rather solve it now !

Thanks

 

[miller]

Or it still could be the new torsion crossmember sockets

Can you elaborate on that? New crossmember sockets?
New, or used, both sockets should be at the same mounted angle. Are they?

Understand (now) about the newer bars hex angles. Back in the day, like I mentioned, they were different by design. Yes, once mounted, and used, they need to go back in that same side. Memory says, in the day, the right side bars had a dab of green paint, midways on that bar. Simply for quick reference, if the bars were pulled for service.

Understand your frustration. Something so simple, or normally is!

 

[Steverino]

Can you elaborate on that? New crossmember sockets?
New, or used, both sockets should be at the same mounted angle. Are they?

Understand (now) about the newer bars hex angles. Back in the day, like I mentioned, they were different by design. Yes, once mounted, and used, they need to go back in that same side. Memory says, in the day, the right side bars had a dab of green paint, midways on that bar. Simply for quick reference, if the bars were pulled for service.

Understand your frustration. Something so simple, or normally is!

Yes the torsion bar crossmember was replaced during the body work

It's an AMD part

The crossmember sockets are oriented with points straight up and down....same as originals I have seen or seen photos of

I'm going to try and make some more precise measurements of the play/differences side to side with an angle finder and see if I can't narrow down the source of this discrepancy and frustration !

It really seems that it can only be either the control arm that I borrowed also has too much slack/play in the socket, or maybe the new torsion bar crossmember sockets have too much play (only on the LH side ?)

 

[miller]

Okay. Not much of a fan of aftermarket stuff. But, ya gotta do what you gotta do.
You might wind up, living with what you have...

(Reminds me of flogging a dead horse.)

 

[5.7 hemi]

I think your problem lies with the pivot pin rotating in the rubber bushing. I’ll explain......I bought some QA1 lca’s and 1” FF tb’s. After installing all the parts, I had a problem keeping the right side where I wanted it. I fought with it for 2 years, called QA1 and was told it wasn’t their part, called FF and Dick said he was sure it wasn’t his tb’s.

So I’m pissed off, yank all that stuff out, install factory lca’s and PST 1.03 tb’s. All is right as rain now.

So I get to looking at the tb’s, they are point to flat, same as factory, so I’m looking over the lca’s and noticed the pivot pin out of the bushing by 1/8”. Grab the pivot pin and I’m able to turn it! WTF! Turns out the pivot pin would rotate as I adjusted for height, not good. QA1 had used crappy lca bushings.

So I’d suggest checking the lca bushing.

 

[Wietse]

Both my LCA bushings are free on the pivot shafts...another story.
I reused the original LCA's and pivot shafts, new MOOG rubber LCA bushings were used.
After using a press to get the bushing onto the shaft i was walking around with it to prepare to press it in the LCA and the bushing just fell off.
Turns out both pivot shafts sit loose inside, most likely caused by "worn" pivot shafts due to new bushings being pressed on over the years and i should replace them.
Only difference here is that i actually do not have to keep the pivot shaft nuts loose when adjusting ride height as they are free to rotate any direction at any time.
As i mentioned, this is the case on both sides on my car so this could not be causing this.
Only issue i could see there happening is that if the bushings are tight on the pivot shafts and you do not loosen the nut and free the shaft, you are taking tension on the torsion bar you also go against the rubber bushing causing extra torsion required to raise the car which could explain the difference in the adjustment bolts.

 

[5.7 hemi]

I disagree. The pivot pin is not to move in order for the lca/tb socket to do their job. If it’s moving, it’s wrong.

 

[Wietse]

I disagree. The pivot pin is not to move in order for the lca/tb socket to do their job. If it’s moving, it’s wrong.

The LCA bushing supposed to be press fit on the pivot pin, on my car both bushings do not sit tight on the pivot pin and can move any time instead of letting the rubber element do it's job.
As you discribed this as a possible root cause, but mine are both loose so that could not be the problem.

 

[5.7 hemi]

Change bushings and get new pins. I’m will to bet that will fix your problem. Since the pivot pins spin in the bushing, that’s not correct, so you solved the problem, now you need r&r the old parts.

 

[Wietse]

Both old bushings were worn and loose as well, but i don't remember seeing any difference in setting. (did not pay attention to it)
I've got new bushings and in the future i will change the pivot pins.
M
For now i can live with the difference in adjuster bolts.

On a side note: If you would use the poly bushings, they also do not have a positive lock on the pivot shaft and also is able to move in axial direction.
If that would really be a problem they would not have came up with that idea i guess....

 

[5.7 hemi]

Poly is a whole ‘nother animal and are meant for the lca to move freely on them. The rubber is supposed to flex in either direction a certain amount.

Just thought of this, the A bodies, some of them have shorter adjuster bolts. Is it possible you have 1 on your car?

 

[miller]

I suggested that he measure both adjuster bolts...he did, they measured the same.

 

[Steverino]

I think your problem lies with the pivot pin rotating in the rubber bushing. I’ll explain......I bought some QA1 lca’s and 1” FF tb’s. After installing all the parts, I had a problem keeping the right side where I wanted it. I fought with it for 2 years, called QA1 and was told it wasn’t their part, called FF and Dick said he was sure it wasn’t his tb’s.

So I’m pissed off, yank all that stuff out, install factory lca’s and PST 1.03 tb’s. All is right as rain now.

So I get to looking at the tb’s, they are point to flat, same as factory, so I’m looking over the lca’s and noticed the pivot pin out of the bushing by 1/8”. Grab the pivot pin and I’m able to turn it! WTF! Turns out the pivot pin would rotate as I adjusted for height, not good. QA1 had used crappy lca bushings.

So I’d suggest checking the lca bushing.

I did replace my lca pivot bushings with moog ones when the frame was being reassembled, and also when I had my lca out (swapping in the e body one to test the torsion socket fit/adjuster slack), my pin is quite snug in the bushing, so I think I'm ok there

I am curious 5.7....were the QA1 lca's the tubular ones ? I believe that's all that's available new , correct ?

And also, I've read some experiences with some newer torsion bars (pst or hotchkis) that the bars are somewhat designed to favor lower than factory ride height(s)

Was that your experience with the pst bars ? And what type of ride height range/"look" do you run/prefer ?

I am admittedly trying to get up to the higher side of spec range...I personally don't favor the fender opening to close to or covering the redline on the front tires

Thanks for the info

 

[5.7 hemi]

QA1’s are tubular. With the bigger bars, installing them is different than the factory size bars. Instead of getting the lca as low as possible, you have the lca set about where you want ride height, almost level to the ground, then install the tb. After that, you set the car down, roll it back/forth, bounce the front end and make any adjustments. Once happy with the height, torque it down.

 

[Steverino]

As an update....I'm more or less narrowing this issue down (I think) to two small clearance issues adding up to too much total slack particularly noticeable in the lh torsion bar

One is the ends of my .096" bars were "dressed" some for ease of fit , although when I spoke with them they did say the bars went in quite "hard" as if it were a very tight fit
In any case, the .096" bars measure at least .002-.003" smaller across the heaxes and across the points when compared to the orig .089" borrowed bars, but I think the .089's just sagged too far under weight masking part of that issue

Second, the crossmember sockets were at a very slightly different angle front to back when measured with angle finder at the bottom of the outside of each tube
RH pointed downward 2 degrees (frt to back) and LH socket was 0
The car was level , and the bottom face of the crossmember was 0 degrees at the same point on each side
So a large bar and a couple hundred pounds of lean (me), and the left one now matches the right

Before reinstalling my lca, I checked all ways of indexing the lh .096 bar (because you can't really check the lca socket to bar clearance by itself when installed) and marked one that felt just a bit more snug and installed that way

I've still got 1/4" more adjuster bolt being used on the lh side, but so far it's sitting level

If I can get the radiator leaks solved....it can get back on the road next week perhaps and we'll see how it "settles out"

Bottom line is I will most likely need to replace these bars
And will NOT be taking the grinding wheel or surfacing discs to new bars before installing

Just haven't decided between 1" FF....maybe another mopar performance .096"

but I'm also going to Carlisle next month so may be able to shop there....but I'll know what I'm looking for now......no shiny ends unless they're truly 1.25" between flats (I'll bring the caliper to measure !)

Thanks for all help and info

I'll report back when it burns some more gas !