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John,You may want to check the shock absorbers before digging into the front end. I believe there was an article somewhere in the forum relating to softening the ride of KYB shocks by removing an inch off the rubber bump stops on the shaft. You would need to grind the weld points on the outer cover to get access to the stops.Hope this works out. Rick
Rick, that information is related on how to add travel to the shock. It won't soften the dampening rate.

When you say the front end is rock hard, please provide some more information regarding the front end. Is it new?, does it have aftermarket torsion leaves? Do you have an anti-sway bar etc etc

Larry I think what John means by rock hard is that when you lean on the front fenders it seems like there is very little give. With the KBY shocks I had on my car it felt exactly the same. I changed to Bilsteins, front and back, and now the front end is even more rock solid than it was before.
My Spyder has a standard ball joint beam (adjustable height - both tubes) with a standard set of torsion leaf springs. No swaybar. I just installed new KYB shocks of the correct length (shock's extension limits not affecting the spring rate). With the front hood removed I can jump up and down on the top beam (I'm 185 lbs.) with very little deflection of the front suspension. The ride isn't all that uncomfortable, but just feel it should have more 'give'. It handles great in autocrosses with zero body lean. Am I crazy to think it should be softer up front, or just forget about it?
John
If you weigh 185 and you jumped up and down on the beam and it didn't move, then I suspect you have a problem. Remove the bottom bolts from your shocks and do the jumping thing again and report back.

More info is needed on the front beam. Was it assembled by a factory, by an individual, has anyone installed Heavy duty torsion leafs as used on off road vehicles, are the trailing arm bushings worn, as you can see, lot's of things could easily be wrong but do as I suggested above and report back
Larry, I tried the 'jumping thing' with and without the shocks. I see a little less damping effect w/o the shocks, but really little difference. I assembled the beam myself and used all new bearings and bushings. The leaf spring sets were ordered from a bug salvage house. I assume that they are used and from a bug. They looked like new. The trailing arms (without the spindle carrier attached) all rotated smoothly (without binding, etc.). Both tubes are full of grease also. I have both beams adjusted for about 5" of ground clearance. My RSK space frame came with the beam welded to it so I can't exchange beams that easily. That's about all I can say.
John
John,
I just went out to the garage and scientifically jumped on my front torsion beams.
Before jumping on the beams I had 25-1/8" from the center of my front wheel arch to the floor. I jumped my 190 Lb. up and down on the front beam 3 times before standing still and (my wife) measured 24" even. So, in my case 190 Lb. on the front beam is pretty much 1" of torsion deflection.

I have ball-joint front, vanilla KYB shocks, and I do have a 3/4" sway bar (but the sway bar doesn't affect the straight up and down bounce). I have something like 19 psi in the front tires, so they may have flattened out a little under my weight -- adding to the measurement difference -- probably only a negligable amount.

My torsion bar leaves are of God-only-knows origin, and could be "relaxed".

Anyway, there is a measurement you can compare too when performing your own Jowdy Jump Test.

Mark
Mark,
You never cease to amaze me with the effort you make to be helpful. Now I'll have to take the time to remove my hood again and perform your calibrated 'deflection jump' test. I should probably wait until after the holidays when my 185 lbs. will be closer to 190. Then we'll be comparing 'apples to apples'. By the way, how high were you jumping? Might as well keep all the variables constant.

I has a similar problem, In my case it was a combination of shocks, the trailing arms binding in the bushings in the beam, front sway bar and trosion leaves designed for a heavier car (VW bug). I addressed all- swap out shocks, skim the trailing arm where it was binding and cut two large leaves in each torsion bundle. Front end is now compliant and doesn't rattle my fillings, even with a stock type sway bar mounting & 3/4" bar. If you cut torsion leaves, section them so you have a full stack at each end and at the center. Tack weld these short end and center sections to the adjacent leaves so they don't move out of position.
Jump = 53.273mm . . . . exactly.

I think Ralph gave you a clue. If you say that you have no noticable deflection when you stand on the beams, even when the shocks are disconnected, then it just might be that the trailing arms are binding against the ends of the torsion tubes -- like the torsion tube is pinched between the two opposing trailing arms.
The trailing arms need to rotate freely on the ends of the torsion beam, and I don't think they should be mashing into the rubber (or urethane)bushing on the end of the torsion beam.

Mark
In a previous post I mentioned that your trailing arms might be "stuck" and you replied that they were free moving. If they are free moving then you should have suspension travel. Did you check them with the torsion bars attached??? If I remember correctly, there is an indent on one of the torsion bars to accept the keeper bolts (inside and outside). Make sure that torsion bar is positioned correctly. Also make sure that the inside is meshing correctly with the keeper bolt.
I just performed a more controlled 'Jowdy Jump Test' using a vertical deflection indicator under my wheelwells. I registered about 1.5", so maybe I'm not so bad off as I thought. I think I'll put off disassembling my suspension for awhile and try my present set up when the snow melts in the spring.
I soffened my front suspension by loosing both torsion bar adjustments then seting ride hight preload with only torsion bar then tightened up the other with no preload. this gives me about 2" of travel as I push down on the nose, hard braking in a bumpy turn will cause the outside tire to just toutch the inner fender. may not be the correct way to do it but makes the front ride over bumps much better.
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