SR-71

They don't squeak, unless they get totally dried out. They're metal-to-metal, so they need lubrication. They don't rattle. But they transmit road noise, so when your tire hits a road seam, that sound is transmitted right up into the body.

I got the polygraphites because they have graphite impregnated into the polyurethane. They're self-lubricating that way, yet you assemble them with joint grease anyway. But they're also ever-so-slightly softer than pure polyurethane. I don't think anyone could tell the difference in handling between the two. My Formula now handles like it's "on a rail."

My shock choice was Monroe Sensa-Trac. "Nicer" ride than Koni or Bilstein. Not quite their handling, but close. Fit my limited budget better. Again, a compromise. They really do "self-adjust" to conditions, though. But I already had WS6 suspension, anyway, which is somewhere between the Camaro's 1LE and Z28. Closer to the 1LE side.

I couldn't tell you what made the most difference for mine, because I did it all in one shot: lowering, bushings, adjustable panhard, boxed lca's, correct geometry (LCA's and FCA's level, and pinion angle square). But the difference from before to after is AMAZING. The only limiting factor in cornering now is tire choice. With "R" type tires, skid pad numbers could push over 1.1 g. And with the rear-end geometry correct, better launch traction and no hop.

I lowered by cutting 2/3 turn off my front springs and 1/3 off the rear. I didn't want to give up the WS6 springs. Slightly stiffer. The Sensa-Tracs help there. But my idea of "perfect ride" is firm enough to feel everything (for road and handling feedback), but no harshness, and quiet.

JunJun

Isn't it a panhard bar's role to absorb the axle's lateral movement?
So if the polyurethane in the LCAs is put into stress in hard cornering, a reinforced panhard bar can be helpful to absorb it.


[quote=91_5.7_TPI;4320668]Rear Lower Control Arm:
While polyurethane is great in sway bars, it looses its shine in places like the rear lower control arms (LCAs). In the LCAs, the polyurethane can create bind in hard cornering. This bind is caused by the LCAs not being able to work as they are designed to. As the rear of the car moves over the rear axle (imagine the axle as fixed and the body as mobile). When the car enters the turn, the body tries to move to the outside of the turn due to momentum, while the axle tries to remain in place (you hope). Now, if taken from a helicopter view, this motion has an effect on the suspension linkages. The most apparent is in the LCAs. As the body moves over the axle, the LCAs are put into stress (bind). The factory rubber bushings allowed for this by flexing and allowing the energy of the movement to be absorbed and dissipated easily. Polyurethane is stiffer than the rubber, and doesn't allow this dissipation so nicely.

SR-71

The answer from "91_5.7_TPI" was correct, but maybe for the wrong reason.

Yes, the panhard bar's role in a 3rd-gen is to prevent the axle's lateral movement. Putting polyurethane bushings in the panhard makes it work better in this regard.

However, the LCA's can still bind in a hard corner, but not from lateral movement. Looking at a tight 3rd-gen from overhead, the body (mostly) stays square over the axle, thanks to the panhard bar.

But looking at it from the rear, you get a different view. The body may not move sideways, but the body will try to roll from the same force "91_5.7_TPI" mentioned. It will try to move to the outside.

It can't slide sideways in relation to the axle, but the body will rotate, It will be lower on the inside of the curve, and higher on the outside. This is trying to twist the LCA's. One end of an LCA is connected to the axle, which is (basically) flat with the road, but the other end is connected to the body, which is rotated.

So polyurethane in the LCA's can be a not-so-good upgrade. If the body rolls enough, and creates enough bind force on the bushings, the LCA will not move up and down properly.

In mine, I thought long and hard about putting polyurethane in my LCA's, or using new rubber. Especially since I "boxed" my LCA's to eliminate twist in them. (Stock "U-stamped" LCA's can twist in cornering, helping with that binding, but also making things a bit sloppy.) I decided that since I was keeping the original WS6 springs and sway bars, body roll was not enough of an issue FOR MY SETUP AND MY GOALS. (<-- Notice this disclaimer! )

I reasoned that perhaps LCA binding might help the sway bar do its job and further reduce body roll. (I don't know if it does or not.) I realized that I might pay a trade-off in handling when cornering on a bumpy surface, and that I might be pulling the LCA's out and putting rubber back in them.

So far for me, polyurethane in the LCA's has paid off very nicely. For someone else's setup, it may not work so well.

hellz_wings

iTrader: (2)

had stock rubber (squishy and loose), then poly (tight but would slide all over the place and almost sent tail spinning multiple times going over uneven or bumpy roads), now have poly/delsphere combo from spohn (PHB and LCA). It works REALLY well, best of both worlds as advertised. Have VERY tight and grippy rear after these.

SR-71: Try putting bigger rear sway bar, stiffer rear springs, remove rear weight or move the rear wheel centerlines to be further out to reduce body roll. I actually had too little body roll in the rear and lowered the PHB alot (I forget how many inches but it was the lowest and only hole on the unbalanced engineering bracket) and relocated the battery to the rear to add rear roll weight which adds traction (in most cases on these cars).

JunJun

Yeah, I agree.
Theoretically speaking, the more the body rolls, the more the poly in the LCA binds, even with a reinforced panhard bar.
But realistically speaking, I don't know how much influence the body roll has on the poly in the LCA, because it seems the body roll itself is slighter than we imagine, especially when some other modification is made in the rear...
At least in my case, with Bilstein and BMR LCAs with poly, I haven't experienced any jumping on a bumpy road when cornering.
(BTW, is this the only way to find "poly binds"? If so, we simply cannot blame poly because there are many other factors that cause jumping!)
So it sounds a bit awkward to me to simply say "polys in the LCA are not a good idea"...

3rdgearslammer

brotherens, i just bought panhard bar rear LCAs front and rear sway bar wonder bar from spohn all del-sphere except for the swaybars and wonder bar. Im trying to find out the torque specs for the above mentioned. Next thing i noticed the rear end links didnt come with new beefier u bolts and nuts whats the diameter for a 10 bolt for new u bolts and nuts, im not trying to screw up these new parts if someone can help me out it would be greatly appreciated.

Donnie(91rs)G

im having some problems here maybe you guys can help me out, when driving down the road at speeds over 45 my 91 rs witha 305 wants to wander, or float if you will, it will just start moving left or right without me moving my steering wheel and when it starts to float to correct it i must move the steering wheel the opposite direction about a 1/4 turn but when im in town the steering it tight and has no play, but does need an alignment, please tell me what the hell is going on!!

SR-71

Sorry I can't tell you specifically, because here is how I find them:

There are several on-line sources for specs and instructions. A new, surprisingly good one is Autozone.com. Go to the bottom of the page at the right, and click Repair Help. Register on the site, register make and model of your car, and there are some decent guides available, usually including torque specs.

Second option, buy a Haynes or Chilton manual.

For Control Arms, lower shock mounts, and any other suspension part with BIG bolts, I just put my air impact on them and rattle 'em down. Those are all assembled with an outer bracket squeezing against a center bushing sleeve. "Tight" is what you're after.

Be sure your bolts are in good condition. If you need to replace them, be sure to get the same length, thread, and hardness as original.

SR-71

You said it yourself. You need an alignment.

First, check all the joints in the steering linkage. There are four tie rod ends (two "inner" and two "outer"), two relay rod ends (one at the steering gear pitman arm, and one at the idler arm), and the idler arm. Be sure they are all tight and solid. The relay rod ends can often be bad, and no one finds it. I had to replace the relay rod on mine a while back. The idler arm is a common failure, too. It should have zero up and down motion.

Second, be sure you have adjusted excess lash out of the steering gear. There are official ways to do it, but I've done it by feel for so many years.... With the engine off, you should not be able to feel any gear lash as you gently move the wheel back and forth. If there is any lash, you can feel the wheel move with no resistance between two high-resistance points. Adjust the lash screw until you don't feel that loose gap between high-resistance points, but no further.

Third, be sure your wheel bearings are tightened down so they have zero play. If you can wiggle the wheel at all, they're too loose. But don't just torque them down, or they'll burn up. When I do mine, I spin the wheel and tighten the bearing nut "tight as I can" using a pair of standard 6-inch slip-joint pliers. Or, I will use a torque wrench and tighten it to 12 ft-lbs. Then I put the lock cap on the nut and LOOSEN IT just until I can get the cotter pin in. (Specs are for 0.001" - 0.005" of play measured at the edge of the brake rotor).

Finally, head for the alignment shop. If you're not sure about the linkage, steering gear lash, or wheel bearings, a good alignment shop will check it all for you. And offer to fix it for a high price.

If everything is OK mechanically, then it's likely that your front wheels are "toed out" (wheels farther apart in front than in back). Normally, front tires are "toed in" slightly (1* to 2*), so when the car is rolling forward, forces cause the wheels to settle back to being parallel. On our third-gens, GM had gotten them tight enough that they thought they could get away with a toe adjustment of 0*.

It's common to toe the tires out for handling contests like autocross. Toe out makes the steering very responsive and quick in low speed maneuvers, but makes the car wander as you describe at high speeds.

Stock alignment specs are pretty good, but can definitely be improved. If you want to improve the handling, here are the specs I use:

• Caster: 4* left. 4-1/2* right.
• Camber: -1/2*.
• Toe IN: 0.2*, or 1/16" - 3/32".

See this link: https://www.thirdgen.org/forums/post...602-post4.html

The difference between right and left caster is because roads are sloped (higher in the center, lower near the shoulders) to drain water.

When I have mine aligned, I go to an alignment guy with a strong reputation. Sometimes you can find one at a tire store, but most often I go to a frame shop. I find a guy who will let me watch, and who will adjust to much tighter tolerances. Stock specs will specify "plus or minus" ranges on the settings. If it's in a range, then it's "good enough." I find a shop that will pull those specs as tightly as possible to my numbers above, as close as possible to "plus or minus zero."

Donnie(91rs)G

Thank you, i have an appt to replace all tie rods and idler arm and pitman arm and get new cross drilled rotors and brakes and have wheels balanced so hopefully she ride smooth now. not sure on how good the shocks are but this thing rides a little rough, is that normal? or is there something wrong here too?

SR-71

That depends on what you mean by "rides a little rough." Mine rides a little rough, but it's a WS6 suspension with slightly chopped springs. So "rough" on mine means "very firm."

If you're talking about rattles in the shock mounts, noisy shocks, or a tendency of the front or rear to bounce more than once over a bump, then you're talking shocks and/or mounts that need to be replaced.

Donnie(91rs)G

it doesn't bounce or make noise, you just feel ever bump in the road, uk of any decent sites to order new cross members? and sway link bars for the rear end? just looking to down size from these bulky stock pieces and maybe pick up a little better handling.

JamesC

iTrader: (5)

Check any of our board's sponsors for after market parts.

JamesC

JunJun

I would also suggest to check A-arm bushings and ball joints, both of which give a bad influence on wheel alignment if worn out.

SR-71

I failed to mention that once I saw the condition of the bushings in my steering cross link, I checked everything else, too. That led to a complete rebuild of the entire suspension and steering system. New poly bushings everywhere. "Boxed" the LCA's, panhard, and every other "U-stamped" piece under there. Only thing I haven't got are a "wonder bar" and strut tower braces. And they're coming soon.

I recommend to everybody that if you find one part worn out underneath, you need to check it ALL. Front and back. If you have a third gen that still has stock bushings, change'em. Even if you use OEM rubber, you'll be fending off lots of potential problems down the road.

Nhertz

I got a quick question. On my camaro the previous owner installed Monroe Senstrac struts and a really annoying thing about them is that they do not have the hex top end for the strut to strut mount bolt. How do you remove the bolt on a strut like that? I have tried using vice grips to hold the top end while I loosen the bolt and it just wont budge. Also holding the dust shield just isnt working out either. I am use to having that hex top end and this is just driving me crazy. Any help would great. Thanks!

rsmith085

iTrader: (1)

I'm assuming your talking about the nut that holds the strut in the strut mount/bearing. I forget what mine has on it but most struts I've seen have what's known as a double d to keep the shaft from turning while loosening the nut. OTC and others make a special socket for it but I've always just used a wrench. Another option is an impact, impact guns work wonders loosening things attached to a shaft that spins.

1 DwnCam

Does anybody have a picture on how to mount the rear sway bar end link? There is a great picture of the front sway bar endlink but not the rear.

Any help is greatly appreciated.

Redroy@live.com

Just picked up shocks, springs, swaybar, ball joints and bushings. I'm hoping I can do this all in my garage, I've been told the A-arm bushings can be really difficult and may require me to take them to a shop to have them pressed out? This is all new to me and have never done camaro suspension, but doing all the research I can!