[gblaue]

Originally Posted by clg82

Hmm interesting.

They call it "SP0779
Suspension Position Sensor Trim Height"

Not saying it's the answer, but it very well could factor that data into the equation of how much power it directs to which wheel when you jump on it.

[radz28]

My car is really bad with the wiggle and sway. While it's several years old (and low mileage), and on the original tires, after adding a little more power than stock, the wiggle/sway was really bad. Even on MT ET Street SSs, in the Summer (90-100-plus degrees), it was bad (even before getting enough street miles to ball-up). I don't think it's the tires, as it does it on the original OEM AND ET Streets. It's bad enough that I've been thrown out of my lane and was headed for the should/ditch more than once. And - it wasn't like it was always a traction-issue. I mean - the tires were on the edge, but the car was going out of control. It gets worse with more power.

Recently, I started a new project and was back to doing some WOT-testing. For engine safety, I pulled all the ALCOHOL timing out of the file (which was as much as 5-7* of advance in some parts of the map), and the wiggle/sway was reduced a fair amount. It was still there, but it was reduced, so power might exacerbate the issue for me. I can see in logs that sometimes it could be a traction issue, but I'm talking 4th-5th-GEAR speeds in Mexico.

I, nearly, replaced as many suspension components (and an alignment) as were available, AND ZLE cradle bushings. That d@mn wiggle/sway was still there.

Not too long ago, I found interesting posts about this that started convincing me it might not be tire or suspension-related completely. Someone posted about THEMSELVES actually contributing to this phenomenon by over-correcting while the wiggle/sway was going on. I started paying more attention (and reflecting on instances where this was happening), and found that the car could start inducing this action, and I would start oscillating the steering wheel because my body was shifting slightly, and THEN a negative feedback loop started to develop where the car would move more, because I was moving more, and I would oscillate as a result, and the car would continue to get worse, and so-on and so-on... After, finally, realizing this, I started to lock into the seat better, start to lock my arms better, and just fight the steering from moving. In MOST instances, this wiggle/sway went away. BUT...

While doing some drivability tuning, I would drag the brakes, and load the engine hard, so I could hit the lower-RPM/higher-load parts of the maps, and even though I wasn't close to over-powering the tires, would just start to nearly DART-around in my lane (this was around 30-50 MPH, BTW). It was so bad I would have to get out of the throttle because it was ALL OVER the place. TC was off, and I was in TOUR. Over time, I found some other comments/threads where people said they found DRIVE MODES might make a difference, so I started trying to compare what happens in SPORT MODE, and low-and-behold... It almost, completely, went away. The wiggle/sway was, pretty much, imperceivable.

I'm still playing with this every time I'm out there. I'm pretty confident, for the car and I, that this is what a large portion of the problem is. Maybe an alignment set-up, more, for the strip would be better, rather than the stock alignment. Maybe I just need to stay in SPORT while I drive. I prefer the ride in TOUR better, but whatever. Maybe someone (or many) will disagree, but that's what I've found so far.

JMHO

[WhiteMale]

All I know is the cradle lockout pretty much took it out, for me. I always held back on the throttle because of it.

[clg82]

Originally Posted by WhiteMale

All I know is the cradle lockout pretty much took it out, for me. I always held back on the throttle because of it.

Same here, which leads me to believe it's the tire pressure at this point. They were at 44psi each after install and i have since taken the recommendations from this thread for PSI, i just haven't had a chance to test it out again.

[seanblurr]

To answer the original question, I get this from time to time as well. When I redo my alignment it seems to go away. If I had to guess, I'd bet it has something to do with rear toe or mismatched rear camber that has drifted slightly from the last time it was set.

[mlee]

Originally Posted by radz28

My car is really bad with the wiggle and sway. While it's several years old (and low mileage), and on the original tires, after adding a little more power than stock, the wiggle/sway was really bad. Even on MT ET Street SSs, in the Summer (90-100-plus degrees), it was bad (even before getting enough street miles to ball-up). I don't think it's the tires, as it does it on the original OEM AND ET Streets. It's bad enough that I've been thrown out of my lane and was headed for the should/ditch more than once. And - it wasn't like it was always a traction-issue. I mean - the tires were on the edge, but the car was going out of control. It gets worse with more power.

Recently, I started a new project and was back to doing some WOT-testing. For engine safety, I pulled all the ALCOHOL timing out of the file (which was as much as 5-7* of advance in some parts of the map), and the wiggle/sway was reduced a fair amount. It was still there, but it was reduced, so power might exacerbate the issue for me. I can see in logs that sometimes it could be a traction issue, but I'm talking 4th-5th-GEAR speeds in Mexico.

I, nearly, replaced as many suspension components (and an alignment) as were available, AND ZLE cradle bushings. That d@mn wiggle/sway was still there.

Not too long ago, I found interesting posts about this that started convincing me it might not be tire or suspension-related completely. Someone posted about THEMSELVES actually contributing to this phenomenon by over-correcting while the wiggle/sway was going on. I started paying more attention (and reflecting on instances where this was happening), and found that the car could start inducing this action, and I would start oscillating the steering wheel because my body was shifting slightly, and THEN a negative feedback loop started to develop where the car would move more, because I was moving more, and I would oscillate as a result, and the car would continue to get worse, and so-on and so-on... After, finally, realizing this, I started to lock into the seat better, start to lock my arms better, and just fight the steering from moving. In MOST instances, this wiggle/sway went away. BUT...

While doing some drivability tuning, I would drag the brakes, and load the engine hard, so I could hit the lower-RPM/higher-load parts of the maps, and even though I wasn't close to over-powering the tires, would just start to nearly DART-around in my lane (this was around 30-50 MPH, BTW). It was so bad I would have to get out of the throttle because it was ALL OVER the place. TC was off, and I was in TOUR. Over time, I found some other comments/threads where people said they found DRIVE MODES might make a difference, so I started trying to compare what happens in SPORT MODE, and low-and-behold... It almost, completely, went away. The wiggle/sway was, pretty much, imperceivable.

I'm still playing with this every time I'm out there. I'm pretty confident, for the car and I, that this is what a large portion of the problem is. Maybe an alignment set-up, more, for the strip would be better, rather than the stock alignment. Maybe I just need to stay in SPORT while I drive. I prefer the ride in TOUR better, but whatever. Maybe someone (or many) will disagree, but that's what I've found so far.

JMHO

Some good observations here.

Might as well add this thread to the list. https://www.camaro6.com/forums/showthread.php?t=500793