Snap oversteer???
 

hi guys,

So i have had this issue with my car at the track.

Around sept of last year my set up was
Custom coilovers
Hankook td
Alignment -3 front -2.6rear

This setup felt great. No issues.


I went to the same track same config this past feb before covid
And my car felt like it was on glass. No other cars were have this issue.
My car on every corner exit would snap oversteer like crazy. I thought it was my garbo driving, but i had a buddy drive my car and he said something is definitely off.

In between track days, i hit this HUGE pothole on the 10 freeway....like this pothole was so big i honestly felt my wheel cracked.
My gf thought we crashed.

Oddly enough i got an alignment, my guy says the alignment was spot on.
All suspension arms and bushings looked great.

What could cause my car to behave so radically in corners?
Any opinions would be much appreciated.
I hope it isnt frame damage. I would literally be okay with any other damage lol

Track was streets of willow cw.

Thanks for you help in advance everyone

Too soft? Causing too much weight transfer? I'm the wrong to guy to ask though thinking back to my go kart days as a kid.

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Thanks for the response.

Not sure but all i know is my set up was exactly the same both times i went. Only difference is me hitting the pothole

Did the pothole cause internal damage to the damper?

Did you get the alignment before or after the car felt wonky? Could have left a bolt loose, or maybe you cracked a cam bolt or something and no one could tell because they didn't remove anything. Weirder things have happened.

what custom valving do you have? i would first talk to your shock guy.

How were your tires? The same ones, more wear, tire pressures?

+1 tires get old, grip less
Some tires get noticably worse sitting in the garage during the "winter" months

Soundman98
I trust my shock guy. I dont think its the problem. He drove my car too and he said they felt fine.

Strat61caster
I did have my tires sit in my garage over the winter.
I live in socal so its not that bad. But maybe letting the tires sit ruined them?. Never thought of that.

Ernest72
Tire pretty i was running were the same as my first mentiined track day. They still had life left. They are my second set of wheels. So they just sit in the garage not used unt track days. Same tire pressure. Slightly more worn, but not nearly enough to make the rear feel like its on glass.

BlueWhalen
I got an alignment before and after. everything seemed fastened down.


Thanks everyone for your opinions. Really helps.
Also i got an alignment and new dd tires. I used tk daily federal rsr. But switched tk their higher TW tire. Their new ST-1 evoluzions.
If i turn the wheel back and forth at highway speeds, the rear feels super floaty.

Maybe i have been blessed tk drive on higher grip tires. But my friends cars who has way crappier tires dont feel like the rear is floating and trailing behind when i make inputs with the steering wheel. Not sure if this problem ks related to my oversteer issue.
But my alignment guy as i mentioned before says everyhing "looks" fine.

Ar all suspension bushings/connections/linkages really fine? Wheel bearings? Are all bolts checked from both sides? (had once head of upper camberbolt snapped, somehow noticed it only when changing winter wheels to summer ones. "it drove fine!")
Do you have by chance alignment printout? Imho more often then not misset toe may cause handling artifacts then camber that you mentioned.
Though that's more along the lines "check everything". By Murphy's laws it will probably be something obvious that noone thought to check or checked last :), just like i checked everything in suspension multiple times in search for noise source, and it turned up loose bracket connection of braided brakeline :/

Sounds like maybe the gas leaked out of one of your struts/coilover/shock absorber whatever you got in there.

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Do you have any additional tire noise while driving? You could have broken belts in the tire causing your sidewalls to crush more than normal in a high g turn. Had this happen to me and drivers side rear sidewall was flexing huge. Car behind me caught it on camera.
Toyo R888R's
Same thing, large pothole on way to the track. 2 laps and my track day was over the car was so bad.

Azzudien: and let me guess - on stationary car tire still looked normal, as damage was inside?

Thanks for all the ideas.

I really hope my struts arent leaking.
XD
As for arms/ linkage, i am totally fine with bent or broken arms /bushings sonce those are replacable.
Im just hoping no one says its frame damage. I am thinking of going into a shop to inspect as well.

Actually the sidewall will starting bulging in some instances. You also will feel it driving. It got substantially worse as I limped home, there was a lot of vibration though never saw any bulge until the tech pulled tire off the rim and he showed me a large bulge inside the tire.
Never heard of it before it happened to me. And frankly I didn't believe the guy at the track that told me this until the tire tech pulled the tire off and explained it all. Apparently not that uncommon in the northeast with our crappy roads

How many track days/sessions on the tires? Most tires lose grip after 10-12 heat cycles even though they have plenty of tread left.

I'd swap the tires front/rear and see if it follows the tires. Was it noticeably worse one side more than the other?

The tires has 2 track days.

I tried rotating the tires. Still same issue. Both left and right turns.
:(

Have you checked for sway bar bind?

Hey steverife,

Not sure what swaybar bind is.
But small update.

Turns out my rear endlinks are totally shot.
The rear lca bushing was shot and the bushing in the knuckle, i can move with my finger. ( theres resistance, but i can still move it.)

Im assuming these are the reasons for my unpredicranle handling.

Has anyone replaced the bushing in the rear knuckle before?

Hydraulic press is your good friend here.

Well you're obviously losing rear grip. Snapping on exit or is it starting to come undone just after mid corner?? Are you on throttle or still off after the apex?

It sounds like a tire pressure issue combined with a small technique issue?

Its coming undone just after the apex.

I am definitely not the most adept driver. Always learning.
But it never felt like thisbefore. Even the slightest bit of gas would cause massive oversteer. Im not the most aggressive driver so it's just strange to me this happened suddenly lol.

I checked my car out. Both boots on my rear endlinks were completely open and oozing grease. Both lca and rear knuckle bushing i can move. The knuckle bushing is more resistant, but if i try hard enough, i can move them with my fingers.

I assume this was the issue. Ha d a shop BRIEFLY inspect my car. No frame damage lol.
I replaced alot of parts. Will prob get it aligned this weekend or next and see if it's any better..

Thanks for everyone's help

Come out to the next 86cup day and i can evaluate the car for you.

They're supposed to move in some directions, but not others so hopefully you aren't tearing it apart for nothing.

Thanks mike for the offer. I might take you up on that in the future.

But i have all of my parts in. And i got it realigned.

While i was at it, i decided to upgrade my outer front tie rod for funzies.

But the bumpsteer is dangerously close to the wheel. Anyone know od solutions to clearance issues for outer tie rods?

My alignment guy says unfortunately rn, its the best he could do. Says theyre like thay by design.

They are very close. Maybe 2-3mm?

Thanks