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Old 02-26-2015, 11:01 AM   #220
ZDan
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Quote:
Originally Posted by RBbugBITme View Post
ZDan, I understand any RC related equations become useless when it is very near the ground plane.
So why plot them and suggest they indicate "bad things"?

Quote:
That doesn't change the fact that when it (or the FAP if you prefer) passes back and forth above and below the ground plane your jacking forces will be constantly reversing direction. That isn't going to be good for stability at the limit of tire adhesion unless you have minuscule jacking forces to begin with. I don't know what typical jacking forces are for this car.
Jacking forces are small when roll center height is near zero. Going from RC height +0.05" to -0.05" isn't going to give any bigger or more profound change in jacking force than going from RC height +0.15" to +0.05".

The fact that it goes from slightly anti-roll to slightly pro-roll is not in itself a huge deal. It's not like the forces go crazy near zero.
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