Phil Ethier wrote:
> http://www.visi.com/mac/icerace.htm
> This is Philip N. "Flip" Shockley leading Peter Kitchak through a
> left-hander. The interesting thing is that both cars are in an
> oversteering attitude and the front wheels on the two cars are pointed
> in opposite directions. This illustrates a basic difference between
> FWD and RWD when ice racing.
Yea verily, it is interesting. And yes, it is a wonderful and graphic
demonstration of fwd vs rwd chassis dynamics on a low grip surface.
> Both cars are in an oversteering attitude
Hmmm?
Well... I don't get that. To me, the Saab seems to be understeering,
and the Porsche oversteering.
At the risk of opening yet another can of worms, here is a definition
of understeering and oversteering that I dimly remember:
Understeering:
When the grip angle at the front (i.e. the angle between the plane of
rotation of the front wheels and the velocity vector) exceeds the
grip angle at the rear (i.e. the angle between the plane of rotation
of the rear wheels and the velocity vector).
Oversteering:
When the grip angle at the rear (i.e. the angle between the plane of
rotation of the rear wheels and the velocity vector) exceeds the grip
angle at the front (i.e. the angle between the plane of rotation of
the front wheels and the velocity vector).
According to these definitions, I believe the Saab is understeering,
and the Porsche is oversteering.
Am I missing something obvious to the contrary?
Regards,
Erik Berg
PS> Boy, does that ice racing look like fun, or what...
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