when i had the spoon x-brace on the car along with the spoon strut brace, the car was very twitchy.. on corners the back wouldn't slide out, it actually skipped as if i hit a lump on the road and the tires left the ground for a split second..

anybody else experience this problem or know what's causing it? i've removed the x-brace since then.. but also modified the suspension quite a bit and r-comps for auto-x..

 

Sorry, can't say I have ever felt the front become twitchy after adding my X-brace and STB. If anything it became much more stable and steering inputs were more direct/precise feeling.

As far as the rear of the car is concerned I can not comment due to the tremendous amount of additional reinforcement I have added back there.

 

I've had similar experiences, but with stock suspension (2002) with SO2's and RA1's. When at around 7/10'ths cornering on a bumpy sweeping turn, the rear either has a wavy "motion of the ocean" wagging or when pushed a little more, a skipping action. It never happens on a smooth track. The rear end response and oversteer is very predictable and controllable. It doesn't happen or isn't noticable when driving at a normal steet-driven pace.

I'm pretty sure the wavy rear feeling is due to the big rear toe changes that happen on the sudden bumps (i.e. the dreaded bump/roll steer). GoFast Labs has that new rear control arm that reduces the toe change vs. suspension travel that should help this out. I suspect the "skipping" feeling when pushed harder is also caused by sudden toe change with the bump, causing momentary loss of traction, but I'm not sure. Could be some other suspension tuning issue.

IMHO, the stiffening shouldn't be the cause of your issues. All it supposed to do is stiffen the chassis to help the suspension work in a more predictable and stable way. Maybe it is just exposing the inherent suspension geometry or tuning issue you are having with your setup.

 

I have a MY 00. At one point, I had an x-brace, a STB and cusco 3-piece bars. With my alignment, I found that combination too sensitive to drive on the street. If you looked to the side, the car would change lanes. I would take off the STB and leave the other bars on for the street, but ran with the STB on (with the other braces) for several auto-x's and it was great.

I have since taken them all off because I run B stock and they are not legal

 

If I understand the converstation, you guys actually think STB's or X-Brace's DO something on an S2000?

 

Actually, from my own experience the X-brace definitely does improve the comfort when driving over rough roads on the street. This is even more apparent if your car is lowered. There is a stretch of really rough road that I have to drive through on the way to work every day (Highway 101 in san jose). The X-brace really makes it much more tolerable.

I doubt it does anything on the track though. In fact, it may have possible negative effects for a S2000 with a purely stock. The S2000 engineers may have factored in a certain amout of flex in the chassis when designing the suspension and the X-brace reduces that flex, so the front toe, camber could be different from what the engineers intended it to be.

 

Exactly. I think there is a huge difference on the street where the roads are much less than perfect, especially here in LA. On the track, its iffy, the turn-in is slightly sharper, but thats about it. Really, the x-brace helps on uneven roads.

 

"IF" such flex exists at OBTAINABLE chassis loads, the suspension geometry would change. It would be pretty damn hard to predict that value. In simplistic terms, when your suspension geometry changes the tires are pointing in directions you didn't originally intend. I think it would be pretty hard to predict the end result there.

IF chassis flex was an issue, and that issue was addressed by the addition of reinforcement, the chassis would theoretically be stiffer. The ride over rough roads would be firmer and even more jarring, it would not be more comfortable.

 

The STB does nothing. The x-brace might have some effect, but doubt it is significant. Was trying to be modder-PC

 

If I remember the catchphrase: "VOTA Rules"