suspention help (torsion bars)

[plydusted]

I have a 1974 ply duster i swaped 6 cyc for 318. front end has always been soft but i had it adjust or up to stock hight. the car doesnt like any weight in it, one side seemes to sag out. does it need to be adjusted more or be replaced. Id like to get the front end more stiff without raising it up any more. Right now it sets about level. (other question) Iv rebuilt the front end somtime ago,and the front end still seems loose. Iv had it alighned time and time again but i eats tires. could it be bad suspention or do i need to rebuild it again. the front end checkes out everything is tight but wont stay alighned.
I would appreciate any sugestions,

[George G. Leverette]

The \6 torsion bas had spring rate of 92 lbs and the 2 bbl V8 had a spring rate of 101 lbs whichshould not effect the handling to a great degree. The first up grade should be to a set of KYB shocks especially for the front end, Summit sells the KYBs for a very competitive price. A primary cause for sag is the adjusting screw loosening allowing one side to be lower than the other, this changes the alignment and will cause tire wear. Use lock tight or a jam nut to secure the ride height adjustment, "Just Suspension" 800-872-1548 is another source for the parts you need if they cannot be bought locally. Mopar Performance sells torsion bars that can stiffen the front end: P5249149 has a 110# rate and P5249150 has a 120# rate. The torsion bar I have on my 74 Duster with 360 is larger than both of these springs and produce the stiffness I like.

[plydusted]

Thanks for the info. do you think 120 would keep it stiff but keep the smooth ride. let me know thanks


ply-dusted

[Ray Bell]

While I'm first to agree that 'shock absorbers' are important and that they're often overlooked, they wouldn't strike me as first base in this incidence...

Dampers (that's the correct term for 'shocks') have the job of controlling spring (or torsion bar) movement, particularly in the rebound phase after hitting a bump. They have no part whatever in holding up the car.

By all means, fit them. But don't expect them to prevent the sag or to prevent the alignment problems.

[plydusted]

My thoughts exact. but what i guess i need to know is can they go bad or do i need to re-adjust the one side to make up for it sagging on that side. I dont want to spend the money if not neccesary just wanted to know if any had simular problem and knew a cure. I belive it needs ajusted but dont want to wast my time and money on re=alining it if they need to be replaced in the first place. i want to do it once and do it right the first time, so all comments will be greatly appreciated, thanks to all that have allready.


ply-dusted

[dave571]

Check for the cross member being rotted where the lower controll arm pin goes though it.

It is common on mopars, and I seeem to see it most on A body cars.

Look between the arm and the member where the stud goes through. If you can see what looks like shiny metal near the whole, the whole is oblong, and the arm moving back and forth.

Easy to miss on a frt end chec, because the torsion bars put a lot of load on the arm. It won't move with a wiggle test. You need a 4 ft bar, to see the movement.

Just a thought.

[Cudadrag]

I had to replace the torsion bars (from the stock 6 cyl to Moparperformance 120#) I am running a big block so there was no considerations but I do know that the back springs (I run SS springs) if modified will defiantly change the front sag. Even with the new bars the rear SS spring sag to the weak side of the front-end a bit (drivers side)

To sum up I replaced the entire front suspension (idler, pitman, ball joints inner and outer tie rods, torsion bars) and run a 3-way drag shock. The front end (I think) is still a little loose and saggy (if there is such a word) but is defiantly livable. I know there is a difference using a B-block big block, but I also think the 74 Duster's front-end suspension is small and light thus will never be super stiff and tight.

A rack & pinion setup would do wonders for an A-body. My 70 Cuda (E-body) has a 72 pinto R/P steering unit (drag car) which works very well. The goal was to make more room for the big Hemi's pipes and lighten for drag use, but the lighter front-end took stress off the torsion bars thus the car is stiffer and tighter. I am not sure how well a Pinto's R/P steering unit would hold up in a road course car, but for street and drag it is a viable option.

IMO

[plydusted]

well thanks evryone ithink ill replace all if i can find some lower control arms.

[Loadrunner]

Before you start replacing parts take a look at the condition of your suspension mounting points as was mentioned above. I had a '72 Demon that started to go through tires. I had it aligned twice at two different shops but the inside of the front tires wore badly. I found out the mounting points for the upper a-arms were so rusted that they were bending (its tough growing up in the Rust-Belt).