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Torsion bar opinions

Started by Those, August 26, 2018, 07:17:31 PM

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Those

Thanks for the replies. Frame is solid so I can rule that out. I haven't taken it to a shop yet because I'm always changing something so it would be a waste of money right now. I bought a camber guage and have the Moog offset UCL bushings. The front control arm is all the way out for caster and I adjusted the back for 1/4 to 1/2 degree of camber. Toe in is 1/8 inch. When I dropped the front 1 inch only the toe in changed. It went to 5/8 of and inch. 73 cuda 4 me. Your thoughts on heavier bars is the same as mine. A stiffer bar would transfer more to the frame. Checked my ride height the factory way today and both sides are the same, 1/8 difference between torsion arm and lower ball joint. Fender lip is 25 inches. I know some guys like that measurement. Good news is it's almost gone at this ride height. I liked the front higher because I have Espo +2 leaf springs on the back and I liked it a bit more level.

73_Cuda_4_Me

I've got 25" lip height, and that is with 14" rims all around... and yes, changing front ride height changes alignment figures...
73 340 `Cuda 727 Auto on Column

BS23H3B

HP2

#17
Since this has existed since you got it and persisted through different wheel/tire and shock combos, Its entirely possible that you have rotors/drums that are out of round. This is unusual, but it does occasionally happen. If you have a dial indicator, you could certainly check the run out. No idea what a spec for this would be, I'm sure there is one, but it would surely be very small to zero.

If you checked the ride height in the factory manner, what were the dimensions before and after your changes? The actual measurement between points A and B.

With the change in bounce from a ride height change, I think it may be a combination of other things. Suspension are designed to work best within a certain range of motion. Higher or lower ride heights than normal combined with standard length replacements shock can create a situation where the suspension is working in a range outside of the range of control by the length of the shocks.  This all magnifies as you get further out from the pivot point of the control arm, so if you look at where the shock is located and its range of motion control, it is only 3-4 inches of total shock travel  up and down that is in the optimum range of control at a stock ride height.

If your suspension was raised up 2" in back and you cranked up the front to make it level, you are to a point that you did not have enough compression travel in the shock to initiate and then fully control the motion, it would top out and spring back and repeat the cycle creating a bounce. Same thing could happen if you were extremely low.  If you were cranked up at the higher end of this, you could effectively only have half an inch or less of compression travel in the shock to control the motion of the springs. normally there would be 1.5-2" of travel. A bump, a dip, or even air stacking up under the car, with original t-bars, can lift the nose to a point there is virtually no travel in the shock. A budget friendly, off the shelf parts store shock is going to have diminished to virtually no control at the ends of its travel.

I'd certainly suggest deciding what your final ride height desired is going to be, then getting a quality shock in a length to match your ride height, then getting your final alignment. Monroe, Gabriel and KYB are not going to be able to do this. QA1, Viking, Bilstein, Fox, and others will be able to. I'd probably recommend talking to Mancini Racing, Firm Feel, or even Hotchkis about it. Handling, while typically going lower, has similar principles to going higher, which a lot of drag racers used to do. You still need to have the necessary control at the desired ride height that allows the suspension to be managed through its motion.





Those

Good points HP2. The rear drums and front rotor/hubs were replaced 2 years ago. I have a $100.00 gift certificate for Summit Racing so do I go for better shocks or new torsion bars. I'll have to think about it but not a bad situation to be in. I do remember 3 years ago I changed from the Monroe's to the KYBs and there was a very slight improvement.

Burdar

Larger bars will require better shocks to control the movement.  If it's a shock issue, larger bars are going to make it worse.  You'll need better shocks either now or later.  I'd start with shocks and get bars soon after.  :alan2cents:

HP2

I agree with Burdar. You need new shocks now and certainly later if you step up the rates. You could opt for single adjustable units to allow you to both tune for your current set up and a future upgrade. Just make sure you get a length compatible with where you want your car to sit. Mopar used to sell extended length shocks specifically for drag racing where ride height s were taller than stock, which is sounds like you have your car at.

Those

Looks like it's shocks first. That's a lot less work than replacing the bars. I'll post back with what I get and the results. On a side note I had a picture of the front in the "attach" box but I'm not sure how to post it.


Those


Bullitt-

.                                               [glow=black,42,300]Doin It Southern Syle[/glow]       

RUNCHARGER

Yes: That's a good looking Cuda, I like the way it sits.
Sheldon

Those

These came today so I'll let you guys know what the difference in ride is between these and the KYB shocks I have know. Thanks for the complements on the Cuda.


Chryco Psycho

I agree the Cuda looks great  :bigthumb:
I have always found KYB shocks are very harsh , the new shocks should be more compliant but with faster control .

Shane Kelley

Quote from: Chryco Psycho on September 16, 2018, 02:28:07 PM
I agree the Cuda looks great  :bigthumb:
I have always found KYB shocks are very harsh , the new shocks should be more compliant but with faster control .
:iagree: I can't stand KYB shocks they are terrible riding shocks IMO. My 71 Road Runner came with a set on it and the car felt like it was floating all over the road. Stuck a set of Monroe gas shocks on it and fixed all the issues. Felt like a whole different car.

Those

I brought my old thread back to say I found the reason for my front end bounce. When I was restoring my Cuda I replaced the power steering gear box and bought a new pitman arm. It seems I've had the wrong pitman arm. The drop was over 1" less than the new one I just installed. I was looking at my tie rod sleeves and noticed the drivers side was a much steeper angle than the passenger side. 5 degrees on the passenger and 10 degrees on the drivers. So I shimmed the gear box to get the drivers side to 7 degrees, went for a ride and no bounce. The angle was causing a bump steer on the drivers side. My guess is when I lowered the torsion bars I was improving the angle enough to eliminate most of the bump steer. With the new arm I was able to remove the shims and raise the front where  I want it. I now have 5 degrees on both sides and the car rides great. Funny how everything was good until I would hit 65 mph then it would start. So many times people post their problems but you neve hear if they found the answer. I hope this helps someone else. Thanks again to all the reply's.

THE ZUKE

Topic relly interesting  :bigthumb: Now I know one thing : I have to change my KYB shocks.  ;)

I don't find them good, what do think about Hotchkis shocks ?