If your wheels weren't balanced properly, and at high speeds, started to shimmy or shake, would the ESC system come into play & brake where needed or slow the car down until the wheels spun without shaking???

Curious to know if C5's have this, either with or without Active Handling...

I am also curious to know if the C5's have some type of lateral speed sensor related to this....

Because........

While racing my car on Saturday, everything was fine for 12 runs, until I swapped rims & tires, (since mine were down to the cord). The first run with my friends rims/tires, the car shook midway down, and it felt like my car's tranny didn't shift...Time was .5 slower

Tried it again, same result, no tranny shift, and same .5 slower

Today, put back on my regular street tires & rims, car shifted perfect at WOT.

So, we are thinking that the wheel shimmy was detected, and either TC or AH or torque management kicked in to slow me down, holding me in gear, making me think it was a tranny issue...(Again, TC/AH were OFF)

Someone mentioned that even though we hit the TC/AH button to off, that its still enabled at like only 5%... Never totallly & completely off....
Is this ture>>??

I will do some WOT runs with new tires & my rims in a day or so, but if everything shifts OK, then there must be some type of wheel sensing system slowing the car as it detects shimmy, even though I de-activated the TC/AH.....

FYI: Tranny temp was about 180, coolant, 190, oil, 205.

Hopefully someone will step up and confirm our thinking, and with balanced tires as before, I will not encounter any problems..


Thought,s comments please....Anyone???
Thanks





[Modified by indypace78, 7:08 PM 11/5/2002]

 

This needs a bump^
Anyone?????

 

up again ^

 

Ellis, were the tires you put on the exact same size? If they were smaller/larger it would effectively change your gear ratio and f*** up all your shift points. There is nothing that would cause your trans not to shift with regards to a shake, but if the shake was bad enough the only thing I can think of is the possibility of shaking around the exhaust,etc enough to make the knock sensor believe there was a knock detected. If the computer cut timing to kill the knock, it could potentially mess up a shift if it pulled timing right before the shift point. Autotap and log your runs, and make sure you record knock retard and ignition timing. If you need help with the a-tap setup email me. :cheers:

 

The tires were the same size 275/40/17, but I'm not sure about the rims. They were sawblades from a C4...


In any event, once home with my HRE's & Pilots, it shifted normally on 2 WOT runs...

The test will be Sat... I have a new set of tires on my rims....So hopefully everything will be OK..

Also, I am getting Tony's tires balanced, but first I am going to have them checked without pulling any of the rim weights off.... Boy, I sure hope they are WAY off!

Joe Signoire used them before me, and also reported a shimmy...

Had I known this, I wouldn't have switched, even though I was down to the cords....

I was doing really kick azz too.... Oh well...

Just hope Tony's tires are way off, or rims are bent...

Gee, if they check out OK, I will be worried big time & holding my breath.

My bet is that they're way off balance...

And that some sort of lateral speed sensor detected the vibration and slowed me down, holding me in gear..............

(Sounds good, doesn't it???)

 

I'll have my autotap with me Saturday, if it's still AFU I'll set it up to log a run for you :cheers:

 

Thanks bro... Who drives my car, me or you?

 

ME!!!!