Very stiff front suspension

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Mopower71

Mopower71

Speed Demon
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Poughkeepsie, N.Y.
My Demons front end is very stiff. Pushing down or pulling up on the car yields very little movement.
It has 888-9 torsion bars, /6, Koni adjustable that are set to the loosest setting, and the front end components are all new. Not poly, just the standard bushings.
I compaired the Koni's to the Doetsch Tech 3 way adjustable (Summit Racing) and the Koni's are much looser.
The torsion bars are not cranked up all the way. When I got the car they were. It had a 340 in it. and when I set my all steel 440 in , it barely moved. I dropped the adjustment so that it would have more upward suspension travel for launch.
It has no bump stops for the upper control arms. And the suspension does move when it is jacked up. but takes a bit for it to sit down after it has been in the air.

What should I look for/ what do you think would be causing the stiffness?​
 
When the suspension was rebuilt and all the control arms tightened up and torqued, was the suspension sitting at normal ride height or was it hanging down while on stands?

If it was the later, the bushings are now in shear and trying to hold the suspension up.
 
I'm unsure, as the new front suspension was already done when I purchased the car.
Might be worth a try to support the lower control arms and loosen everything and then re-tighten.
 
Make sure that the lower control arm rubber bumper is not making contact. If it is, the torsion bars are not loaded or not loaded enough or they could be broken or the mounts are broken.
 
The lower control arms aren't touching.
I had to adjust the front end down after I got the car because they were way to high. They adjust and they are not broken.
The suspension does move up and down, it's just very stiff.
 
from the text, I'm guessin it was like this when you got it. Here's what I would do. Get it on a drive on rack where it will be supported by the tires. Get under it and loosen up ALL the control arm mounting bolts. It sounds like somebody torqued somethin down while the wheels were in the air. Be careful though, cause if you find an offendin joint, the car could drop down some. I'd do the same for the strut rods, too. It wouldn't hurt. when you get them all loosened up good, jounce the heck out of the front end, let it settle down and then retorque it all back.
 
Koni's are typically very stiff. If you had an old pair of oil charged shocks laying around that you could try, just to see if the issue is with the shocks?
 
I am very interested in this because I have my whole front end torn apart for new bushings. Does anyone have a link to the correct procedure for tightening down the control arms? Can I just support the lower control arm with a floor jack and tighten everything up? Any help would be appreciated.
 
BrianT said:
I am very interested in this because I have my whole front end torn apart for new bushings. Does anyone have a link to the correct procedure for tightening down the control arms? Can I just support the lower control arm with a floor jack and tighten everything up? Any help would be appreciated.
Click to expand...

Just as I described above,the suspension bolts are supposed to be torqued with the weight of the car on the tires.
 
Thanks for the help Guys.
I'll loosen everything up, and recheck.
I might loosen the adjusters for the T-bars, unbolt the lower ball joint and see if I can find the offender.

Does anyone have the torque specs handy, for all the front end components?
 
I removed the shocks, loosened both ends of the strut rod on the passenger side, push the passenger fender down car drops comes back up and stays. It does not bounce up and down like it has no shocks on it. It's not as stiff to push it down, or pull it up.
Next I jacked the car up, loosened up and removed the torsion bar adjuster. Found the lower control arm nut loose, just snug, not much more.
Tried to pick the rotor up to move the suspension. feels like it weighs 50+ pounds just to move it upward.
The upper control arm rubber bushings don't appear to be binding as you can see them rotating, and not twisting.

Am I wrong in assuming with the strut bars loose and the shocks out, it should bounce up and down a few times?

Is it time to pull the torsion bars out and remove the lower control arm?

Anybody have the torque specs for the suspension nuts and bolts?
 
Upper ball joint...125 ft-lb minimum
Lower nut...100 ft-lb
Upper nut...55 ft-lb

Control arm
Pivot shaft nut...130 ft-lb
Rebound bumpers...200 in-lb

Crossmember bolts...150 ft-lb
Engine mount bolts...85 ft-lb

Idler arm stud nuts...
...at center link...40 ft-lb
...at mounting bracket...40 ft-lb

Shock absorber nuts - front
...Lower...50 ft-lb
...Upper...25 ft-lb

Steering gear mounting bolts...80 ft-lb
Steering knuckle bolt nuts...100 ft-lb
...Disc brakes...115 ft-lb

Strut nuts
Front...40 ft-lb
Rear...110 ft-lb

Sway eliminator shaft
...Frame bracket bolt nut...200 in-lb
...Link insulator retainer bolt nut...100 in-lb
...Link to frame bracket nut...100 in-lb

Tie rod ends
...Sleeve clamp...150 in-lb
...Stud nuts...40 ft-lb
 
What are you comparing the stiffness to? I would expect with all new components up front that it would be a good bit tighter, or stiffer, than it was. What do you have for a rear suspension? Does the rear have the same stiffness to it, or can you get some bouncing back there?

It is unclear to me from your description whether you have loosened up both sides (UCA's and torsion bar) or only the passenger side. If you've only done the one side, I would do them both.
C
 
A Mopar typically will not "bounce" in the front like cars with coil springs or strut suspension. I pushed down on both front corners of my Demon today after thinking about your post. Very little movement up or down.

Is there a particular issue w/ the stiffness of the car? Just thinking out loud and trying to help.......:scratch:
 
I just didn't think it was normal to push down on the front of the car and it stays where you pushed it to, or pulled it up to. I would think it would want to at least go back to center.
Good thing I dug into the front end or I would not have fount the lower control arm nut loose.
 
I just didn't think it was normal to push down on the front of the car and it stays where you pushed it to, or pulled it up to.

This would be a completely different question....
Are the torsion boxes rotted out? Which torsion bar is on which side? There is a left & right to them. I don't know why the car would stay down if pushed down, or stay up if it were pulled up.
C
 
888R is on the right side. 889L on the drivers side.
The boxes are not rotted out.
Just put the passenger side back together, tightened and torqued with it in the middle of travel.
 
Mopower71 said:
Good thing I dug into the front end or I would not have fount the lower control arm nut loose.
Click to expand...

Silver lining right there! Nice find!

Still thinking about your posts. How does the car ride and drive? I can't remember, drag car only or double duty?
 
Said you could se upper control arm bushings rotating......but did you loosen them and retorque them? I mean.......at this point, I wouldnt leave any stone unturned. No matter how small. Also another thing to check. Are any of the ball joints binding? I know it would be very unlikely to have one on each side.....but stranger things have happened. You gotta problem somewhere.
 
It sounds to me like a bushing is binding. Rubber suspension components are designed to twist for the suspension movement.

What about greasing the bushings.. That way you will know for sure if they are binding or not. do the bushings Squish when you tighten the bolts?
 
Car was for the Drag strip, but is now a street car, possibility of some track time.
I did spray wd40 on the lower control arm pivot, as it had a weird noise like pebbles were in it. It seemed to loosen up.
 
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