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suspension--tail swings out a bit at first stage of sharp cornering/turning

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exdeath

Lifer
Jan 29, 2004
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10
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After clutch replacement, steering wheel alignment off 10 degrees. Already paid. Should I make clutch shop pay to fix alignment?

Why were your tie rod ends or steering shaft molested just to do a clutch?

I can see steering shaft in the way maybe if it's a front steer rack. So as long as the tie rod ends weren't messed with you can just disconnect the steering shaft and move it one spline and it only affects steering wheel center and has nothing to do with toe setting.
 
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Dec 30, 2004
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No need to be a dick about it.

You could try a front strut bar or a stiffer front sway bar.

The trouble you are asking for is a further increase in oversteer. More RSB stiffness -> more oversteer as I (and others) have reiterated.

First of all, I did not say that the dampers snap, I'm not sure how you got that out of what I wrote. This has very little to do with the coil springs and everything to do with the sway bar. What a sway bar does, ostensibly, is to increase the spring rate (more properly - the wheel rate) of a car's suspension during roll (i.e. during a corner). While the dampers may do well to control the suspension's coil springs over bumps in the road they will struggle to control the added wheel rate of stiffer sway bars in roll. The dampers are not 'working in tandem' because both springs aren't compressing when the car rolls/corners - one side is compressing and the other side is drooping. The 'snapping' feeling some drivers report from using too-stiff sway bars is a result of the dampers being unable to control the sway bars' motion as a car exits a corner and the sway bars try to return to center.

What on earth is the "firewall spring effect?"

Now, before you get all "I gotta have no body roll!" seriously consider the ramifications of a further increase (I did not use the word "upgrade" on purpose) in your roll bars' stiffness: (1) you're reducing the independence of your independent suspensions, which will result in a loss of grip; (2) the added wheel rate of stiffer sway bars will overwhelm your dampers, which can only be adjusted in compression, resulting in a loss of grip and vehicle stability; (3) you'll increase the likelihood of jacking down your suspension, which results in instability and a loss of grip; (4) you might start approaching the limits of your end-links and chassis, where you'll start breaking components and/or the torsion stiffness of the chassis becomes your limiting factor (which has virtually no damping).

step-out-- it feels like a useful term for a specific subset of "oversteer" where the wheel isn't close to breaking loose

snap-- obviously it's not the dampers snapping, it's the springs. My point was that if the dampers work with the spring, then a sway bar shouldn't be any different-- from the perspective of the shock/spring, wheel loaded or not, the effect is the same-- pressure on the spring. That the wheel itself is unloaded, is a good point I had not considered.

Firewall spring effect would be the closest thing you can imagine it referencing-- firewall's "spring rate" is not as stiff as stiffer springs+sway bar, and as a result ("end-links and chassis" for example) exhibit greater compression than with stock springs.

What would be a good rule of thumb re: sway bar stiffness "upgrades"?
Are you saying these guys at Hotchkis shouldn't have released this product?
 
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Why were your tie rod ends or steering shaft molested just to do a clutch?

I can see steering shaft in the way maybe if it's a front steer rack. So as long as the tie rod ends weren't messed with you can just disconnect the steering shaft and move it one spline and it only affects steering wheel center and has nothing to do with toe setting.

I don't know, because they're idiots? No really, I don't know, are they idiots? I think it was in the way. I kept telling them it wasn't the transmission but they thought it was, perhaps they were prepped to remove the transmission?

Steering shaft-- if it technically doesn't track straight by itself when coasting (pulls), is that really a steering shaft problem?
If it were, is this something that could have changed?
 

exdeath

Lifer
Jan 29, 2004
13,679
10
81
Maybe you should visit and ride in JLees MR2 or my Cobra and decide if that's really what you want. Your tailbone will hate you if it's your only vehicle.

Cobra is factory suspension even but you still feel like you have to brace for every crack in the road and make sure your tongue is secure.

"Race cars" are tuned for prepped and maintained tracks. Real world roads suck.
 
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Maybe you should visit and ride in JLees MR2 or my Cobra and decide if that's really what you want. Your tailbone will hate you if it's your only vehicle.

Cobra is factory suspension even but you still feel like you have to brace for every crack in the road and make sure your tongue is secure.

"Race cars" are tuned for prepped and maintained tracks. Real world roads suck.

I don't feel like I'm anywhere near that...still plenty comfy
 

OverVolt

Lifer
Aug 31, 2002
14,278
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91
Once you stop trying to tune the car to be RWD and tune it the best you can for how it really handles you'll be in better shape :)
 

JCH13

Diamond Member
Sep 14, 2010
4,981
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step-out-- it feels like a useful term for a specific subset of "oversteer" where the wheel isn't close to breaking loose

snap-- obviously it's not the dampers snapping, it's the springs. My point was that if the dampers work with the spring, then a sway bar shouldn't be any different-- from the perspective of the shock/spring, wheel loaded or not, the effect is the same-- pressure on the spring. That the wheel itself is unloaded, is a good point I had not considered.

Firewall spring effect would be the closest thing you can imagine it referencing-- firewall's "spring rate" is not as stiff as stiffer springs+sway bar, and as a result ("end-links and chassis" for example) exhibit greater compression than with stock springs.

What would be a good rule of thumb re: sway bar stiffness "upgrades"?
Are you saying these guys at Hotchkis shouldn't have released this product?

1) Convention/terminology doesn't care what you think. Oversteer is oversteer. It can be mild and predictable like what you are experiencing, or it can be dramatic and unpredictable. Next time you get a little oversteer lift throttle and then step on the brakes and then tell me it's not close to losing traction (careful, this could cause your car to spin).

2) Wow, I shall try to address all the fallacies and incorrectness here... The springs, dampers, sway-bars, suspension, etc are all mechanically linked, so they all experience the same motion. The dampers do work with the spring similar to how they work with the sway bar. However, the damper can only control a certain spring rate. The coil spring and sway bar both contribute to the effective spring rate the damper must control (the wheel rate). After the sway bar gets twisted up in a turn and starts to unwind after the turn the damper is there to control this motion. However, if the ARB is too stiff, the damper can't slow down the suspension's motion properly. This situation is 'under-damped' and is very essentially the same as using springs that are too stiff for your dampers. But, because it is different than an underdamped suspension, many describe the feeling as the car 'snapping' back to center out of a turn.

3) So "firewall spring effect" is another way of saying "the chassis is too floppy." I wish you would just use the right terms for various phenomena, it would make life easier.

4) I am not familiar with the tC's chassis, I don't know what would be too stiff. I wouldn't go over 2.5x or 3x stiffer on principle. If you're asking "do you think an aftermarket company would make a product that is ill-suited and poorly designed for its intended application" then the answer is yes. There are plenty of companies that make shitty aftermarket suspension components without understanding good suspension design. It's possible a stiffer sway bar could work well if the chassis received substantial bracing.

Please look at what you know with a little bit of skepticism instead just assuming what I'm telling you is incorrect because it conflicts with your assumptions.

Once you stop trying to tune the car to be RWD and tune it the best you can for how it really handles you'll be in better shape :)

This. It sounds like you are trying to make a porky FWD car handle like a high-end sports car with cheap components and it isn't going to happen.
 
Dec 30, 2004
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1) Convention/terminology doesn't care what you think. Oversteer is oversteer. It can be mild and predictable like what you are experiencing, or it can be dramatic and unpredictable. Next time you get a little oversteer lift throttle and then step on the brakes and then tell me it's not close to losing traction (careful, this could cause your car to spin).
yes, I am very familiar with this experience D: it's what I was referring to when I mentioned braking (uh, breaking works here too) while turning
2) Wow, I shall try to address all the fallacies and incorrectness here... The springs, dampers, sway-bars, suspension, etc are all mechanically linked, so they all experience the same motion. The dampers do work with the spring similar to how they work with the sway bar. However, the damper can only control a certain spring rate. The coil spring and sway bar both contribute to the effective spring rate the damper must control (the wheel rate). After the sway bar gets twisted up in a turn and starts to unwind after the turn the damper is there to control this motion. However, if the ARB is too stiff, the damper can't slow down the suspension's motion properly. This situation is 'under-damped' and is very essentially the same as using springs that are too stiff for your dampers. But, because it is different than an underdamped suspension, many describe the feeling as the car 'snapping' back to center out of a turn.
so I understand what you're saying, but I can't see that the damper would be snapping with extra force coming through the swaybar from the other spring on other wheel-- if each spring were sufficiently damped without a sway bar, then during unloading that spring wouldn't contribute any extra force through the sway bar to the other damper unless one had a stronger/weaker damping coefficient on one side. What I do see happening is the spring on the outside of a turn compressing less with a stiffer sway bar than it would otherwise, similar to how a capacitor would charge half as much, given the same current, when in parallel with another capacitor.

3) So "firewall spring effect" is another way of saying "the chassis is too floppy." I wish you would just use the right terms for various phenomena, it would make life easier.
fish flop. wouldn't flimsy be a better word? but yes, words are imprecise pointers, and I've never been good selecting the right one...
4) I am not familiar with the tC's chassis, I don't know what would be too stiff. I wouldn't go over 2.5x or 3x stiffer on principle. If you're asking "do you think an aftermarket company would make a product that is ill-suited and poorly designed for its intended application" then the answer is yes. There are plenty of companies that make shitty aftermarket suspension components without understanding good suspension design. It's possible a stiffer sway bar could work well if the chassis received substantial bracing.

Please look at what you know with a little bit of skepticism instead just assuming what I'm telling you is incorrect because it conflicts with your assumptions.
I can see that happening. Do you think Hotchkis has enough knowhow and wisdom to not do something like that? Does their brand carry any value or weight?
This. It sounds like you are trying to make a porky FWD car handle like a high-end sports car with cheap components and it isn't going to happen.

Yeah. I think I'm finally happy with how it's performing now, may experiment with stickier rear tires, and a front strut brace if anyone thinks it might benefit. Now if I could just get ride of the lower control arm rocking ball joint on my driver side wheel....but I think that's probably never going to happen
 
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now less oversteer with the alignment.

front sway bar being so stiff causes both wheels to react to pot holes or manhole covers. bad!

hard to say if strut tower mount provided any improvement. Oh well, it was $90 just to see.

won't be doing any more upgrades. If I want better will just get a BMW.