C7 General Discussion General C7 Corvette Discussion not covered in Tech
Sponsored by:
Sponsored by:

Tight turn tire dancing...

Thread Tools
 
Search this Thread
 
Old 11-13-2013, 10:10 PM
  #1  
Rad22
Burning Brakes
Thread Starter
 
Rad22's Avatar
 
Member Since: Mar 2013
Posts: 1,135
Received 14 Likes on 10 Posts
Default Tight turn tire dancing...

I know this is considered "normal behavior", but has anyone else noticed it getting MUCH worse with the advent of colder temps or is it just me? My wife says "You need to get that fixed! It's embarrassing."

Actually, she's right. In a small restaurant parking lot tonight, with a few peeps standing around watching "the new Vette" leaving, it skittered and jumped like crazy...much more than ever before in my 2800 miles.

What gives?

Also, could someone with a good command of the English language explain exactly what's going on? I've never owned a car that did this.
Old 11-13-2013, 10:18 PM
  #2  
Old Yellow
Pro

 
Old Yellow's Avatar
 
Member Since: Jan 2010
Location: Freedom PA
Posts: 628
Received 62 Likes on 35 Posts

Default

It is the result of the Ackerman steering angle geometry being adjusted to favor high speed driving at the expense of slow speed turning. Cold temperatures affect the grip of the tires, and make it more noticeable. So yes it does get worse at colder temps.

For a good explanation of "Ackerman steering" do a Google search of the term. I highly recommend you at least read Wikipedia's article first.

It is normal for a high performance handling automobile. Most of us have never driven automobiles that were engineered for ultimate handling, and were never exposed to this behavior.

You don't need a mastery of the English language, but experience in automotive handling dynamics.

Ed

Last edited by Old Yellow; 11-13-2013 at 11:34 PM.
Old 11-13-2013, 10:55 PM
  #3  
Red Lightening
Racer
 
Red Lightening's Avatar
 
Member Since: Oct 2013
Posts: 331
Likes: 0
Received 2 Likes on 2 Posts
Default

Does the C6 do this as well? I never noticed this. I don't think this kind of steering behavior is suitable for any car sold to be driven as a daily driver.

Last edited by Red Lightening; 11-13-2013 at 11:07 PM.
Old 11-13-2013, 11:00 PM
  #4  
Snorman
Scraping the splitter.
Support Corvetteforum!
 
Snorman's Avatar
 
Member Since: Jun 2005
Posts: 8,115
Received 1,028 Likes on 486 Posts
St. Jude Donor '13-'14-'15

Default

Originally Posted by Red Lightening
Does the C6 do this as well?
Since you apparently have one, shouldn't you already know the answer to this question?
BTW...weren't you previously banned? You avatar picture is the same as one posted by a previous member who frequently bragged about also owning an SSR (lmao). He also bragged about being in the motion picture business, and told people that he could get them Bowling Green tours.
S.
Old 11-13-2013, 11:00 PM
  #5  
budgreen3564
Melting Slicks
Support Corvetteforum!
 
budgreen3564's Avatar
 
Member Since: Nov 2007
Location: McKinney, texas DPD Sergeant
Posts: 2,914
Received 238 Likes on 128 Posts

Default

Originally Posted by Red Lightening
Does the C6 do this as well?
Yes
Old 11-13-2013, 11:02 PM
  #6  
rcallen484
Race Director
 
rcallen484's Avatar
 
Member Since: Dec 2011
Posts: 10,355
Likes: 0
Received 11 Likes on 10 Posts
Default

Originally Posted by Snorman
Since you apparently have one, shouldn't you already know the answer to this question?
S.
Yeah, all us C6 owners learned about this very early on. What gives?
Old 11-13-2013, 11:22 PM
  #7  
Red Lightening
Racer
 
Red Lightening's Avatar
 
Member Since: Oct 2013
Posts: 331
Likes: 0
Received 2 Likes on 2 Posts
Default

Originally Posted by rcallen484
Yeah, all us C6 owners learned about this very early on. What gives?
I don't have a noticeable chatter issue when making tight turns. Not at all.

Last edited by Red Lightening; 11-13-2013 at 11:27 PM.
Old 11-13-2013, 11:25 PM
  #8  
Red Lightening
Racer
 
Red Lightening's Avatar
 
Member Since: Oct 2013
Posts: 331
Likes: 0
Received 2 Likes on 2 Posts
Default

Originally Posted by Snorman
Since you apparently have one, shouldn't you already know the answer to this question?
BTW...weren't you previously banned? You avatar picture is the same as one posted by a previous member who frequently bragged about also owning an SSR (lmao). He also bragged about being in the motion picture business, and told people that he could get them Bowling Green tours.
S.
Old 11-13-2013, 11:27 PM
  #9  
Snorman
Scraping the splitter.
Support Corvetteforum!
 
Snorman's Avatar
 
Member Since: Jun 2005
Posts: 8,115
Received 1,028 Likes on 486 Posts
St. Jude Donor '13-'14-'15

Default

Originally Posted by Red Lightening
No...that's you. I remember that house in the background.
You used to be TorchedC6 or something like that. You ended up getting banned. You also had pics of an SSR and started a thread that you could get people tours of BG because you knew people there and let them on movie sets.
S.
Old 11-13-2013, 11:28 PM
  #10  
rcallen484
Race Director
 
rcallen484's Avatar
 
Member Since: Dec 2011
Posts: 10,355
Likes: 0
Received 11 Likes on 10 Posts
Default

Originally Posted by Red Lightening
I don't have a noticeable issue when making tight turns. Not at all.
The laws of physics dictate that it occurs because of the Ackerman angle and width of tires. It doesn't happen other than very slow, very tight turning maneuver commonly encountered only in parking the car.
Old 11-13-2013, 11:32 PM
  #11  
Red Lightening
Racer
 
Red Lightening's Avatar
 
Member Since: Oct 2013
Posts: 331
Likes: 0
Received 2 Likes on 2 Posts
Default

Originally Posted by Snorman
No...that's you. I remember that house in the background.
You used to be TorchedC6 or something like that. You ended up getting banned. You also had pics of an SSR and started a thread that you could get people tours of BG because you knew people there and let them on movie sets.
S.
WOW this forum just gets nuttier and nuttier with every passing day.
Old 11-13-2013, 11:33 PM
  #12  
rcallen484
Race Director
 
rcallen484's Avatar
 
Member Since: Dec 2011
Posts: 10,355
Likes: 0
Received 11 Likes on 10 Posts
Default

Originally Posted by Snorman
No...that's you. I remember that house in the background.
You used to be TorchedC6 or something like that. You ended up getting banned. You also had pics of an SSR and started a thread that you could get people tours of BG because you knew people there and let them on movie sets.
S.
This picture Snorman?
Attached Images  
Old 11-13-2013, 11:37 PM
  #13  
Snorman
Scraping the splitter.
Support Corvetteforum!
 
Snorman's Avatar
 
Member Since: Jun 2005
Posts: 8,115
Received 1,028 Likes on 486 Posts
St. Jude Donor '13-'14-'15

Default

Originally Posted by rcallen484
This picture Snorman?
Yep. He had another picture of an SSR in the driveway too with a different camera angle.
This was the same person who claimed they could get people in for BG tours because he returned the favor by letting them tour movie (or TV) studios where he works. He took a lot of flack in that thread and it was eventually locked.
S.
Old 11-13-2013, 11:47 PM
  #14  
rcallen484
Race Director
 
rcallen484's Avatar
 
Member Since: Dec 2011
Posts: 10,355
Likes: 0
Received 11 Likes on 10 Posts
Default

Originally Posted by Snorman
Yep. He had another picture of an SSR in the driveway too with a different camera angle.
This was the same person who claimed they could get people in for BG tours because he returned the favor by letting them tour movie (or TV) studios where he works. He took a lot of flack in that thread and it was eventually locked.
S.
I remember that bizarre thread. Well, at least the avatar pic is now preserved in case it gets "updated".
Old 11-13-2013, 11:53 PM
  #15  
Red Lightening
Racer
 
Red Lightening's Avatar
 
Member Since: Oct 2013
Posts: 331
Likes: 0
Received 2 Likes on 2 Posts
Default

Originally Posted by rcallen484
The laws of physics dictate that it occurs because of the Ackerman angle and width of tires. It doesn't happen other than very slow, very tight turning maneuver commonly encountered only in parking the car.
I don't have this issue on either of my C6s. Sounds like an engineering defect to me. Unacceptable for any street car.
Old 11-13-2013, 11:56 PM
  #16  
theseal
Drifting
 
theseal's Avatar
 
Member Since: Feb 2005
Posts: 1,334
Received 52 Likes on 27 Posts

Default

Originally Posted by rcallen484
The laws of physics dictate that it occurs because of the Ackerman angle and width of tires. It doesn't happen other than very slow, very tight turning maneuver commonly encountered only in parking the car.
Its actually insufficient ackermann to be exact, and i cant for the life of me understand why the c5-7 is under ackermanned. It hurts performance badly at all realistic cornering speeds, and the tighter the turn the more it demolishes front end grip. Unless it was a packaging issue, the only reason for it would be to induce understeer by reducing front grip- worst of all worlds.
Old 11-13-2013, 11:57 PM
  #17  
Red Lightening
Racer
 
Red Lightening's Avatar
 
Member Since: Oct 2013
Posts: 331
Likes: 0
Received 2 Likes on 2 Posts
Default

Originally Posted by Rad22
I know this is considered "normal behavior", but has anyone else noticed it getting MUCH worse with the advent of colder temps or is it just me? My wife says "You need to get that fixed! It's embarrassing."

Actually, she's right. In a small restaurant parking lot tonight, with a few peeps standing around watching "the new Vette" leaving, it skittered and jumped like crazy...much more than ever before in my 2800 miles.

What gives?

Also, could someone with a good command of the English language explain exactly what's going on? I've never owned a car that did this.
What you describe is not normal to that excess. It sounds more like an engineering geometry failure to me. GM will fix it in the future I'm sure. It will be one of those quiet engineering changes so not to bring attention to the fact the earlier cars were screwed up and avoid having to fix thousands of cars with the issue.

Last edited by Red Lightening; 11-14-2013 at 12:13 AM.

Get notified of new replies

To Tight turn tire dancing...

Old 11-13-2013, 11:57 PM
  #18  
FrancisDGarcia
Racer
 
FrancisDGarcia's Avatar
 
Member Since: Oct 2013
Location: Snohomish WA
Posts: 357
Likes: 0
Received 0 Likes on 0 Posts
Default

Hmmm....
Old 11-14-2013, 12:02 AM
  #19  
rcallen484
Race Director
 
rcallen484's Avatar
 
Member Since: Dec 2011
Posts: 10,355
Likes: 0
Received 11 Likes on 10 Posts
Default

Originally Posted by ramey
Its actually insufficient ackermann to be exact, and i cant for the life of me understand why the c5-7 is under ackermanned. It hurts performance badly at all realistic cornering speeds, and the tighter the turn the more it demolishes front end grip. Unless it was a packaging issue, the only reason for it would be to induce understeer by reducing front grip- worst of all worlds.
And yet by all both measureable (skid pad, slalum, etc.) measures they do well, all drivers' reviews of the C7 I've seen have been glowing and I, personally, can vouch for how my C6 corners. Go figure.
Old 11-14-2013, 12:06 AM
  #20  
Old Yellow
Pro

 
Old Yellow's Avatar
 
Member Since: Jan 2010
Location: Freedom PA
Posts: 628
Received 62 Likes on 35 Posts

Default

Check my post #2.

Reverse Ackerman angle is used to counteract the affects of differing slip angles of the front tires during high speed cornering.

If you want to brag about your cars low lap time, and high Gs' on the skid pad, that some magazine reported, then this is what helped achieve those high numbers.

Just part of the cost of bragging rights even if you will never take advantage of the cars capabilities.

Ed


Quick Reply: Tight turn tire dancing...



All times are GMT -4. The time now is 05:52 PM.