I know this thread is a little old and got sidetracked, but I'm a bit
behind in my mail and thought I'd address this a bit. First off, power
has little to nothing to do with skid pad numbers. The point is to get
the car on it's traction limit around a circle. There are two ways to
drive a skid pad: On an off the throttle and aggressively sliding around
the pad. That's the slow way. The fastest drivers around a skid pad sit
at just the right speed so the tires' slip angle is matched with the
car's tangent to the circle (ideally). So as long as an engine can
physically get the car to the proper speed and you have as much time to
get there as you need, power doesn't make a rat's ass of a difference, to
be blunt.
Second, you might think weight is an issue, but at actually has a
negligible effect due to physics that would bore everyone to death.
So how do you get a good skid pad number? Low center of gravity, stiff
suspension to keep the tires planted flat (and get maximal contact
patch), good weight distribution over the four tires, and a good driver.
Tires are pretty much the single most important variable. If you put 3
ft. wide tires on the car, it would stick like glue. Downforce can also
improve this tremendously on a big, fast skid pad, but this is a moot
point here. The Tiger's extra power is useless, extra weight would have a
small pejorative effect, but larger tires (?) would more than compensate
for the weight. Most average modern sports cars are in the .8-.95 g
range, with the new Corvette (gag) pushing the envelope to over 1.0. Oh well.
I actually do know what I'm talking about--at least regarding this. I run
the testing program for my school's Formula SAE team (and am a driver) and
one of our competition events is a skid pad, so we've done a lot of skid
pad testing. Our car pulls over 1.3 g on a cold day (not many warm days
in Ithaca, NY). If you're interested, check out our web site:
http://cadstudio.mae.cornell.edu/fsae/
Hope I cleared this up a little.
AM
On Tue, 14 Oct 1997, Anthony Robinson wrote:
> I wrote
> >>The Car and Driver report of 1960 tested the Alpine in a Road research
> >>Report.
> >>On a 200 ft diameter skid pan they got a maximum speed of 48 mph.
>
> Jarrid wrote:
> >Math looks good, but the 80 series tires used on the 60s alpines would not
> >have given quite so impressive figures.
> >
> >Perhaps the testing method has changed between now and then,
> >like if they took a dive into a turn at 45 and the car didnt go into a
> >spin, that means the car handles right?
> >
> >
> >Jarrid Gross
> >
>
> They say that they started out slowly turning constantly to trace a 200 ft
> diameter circle gradually builing up speed until either the car wouldn't
> stay on the road or wouldn't go any faster.
>
> They stated that the top speed was 48 mph true in third gear when the car
> was not sliding out but wouldn't go any faster. They said that perhaps the
> 4.22 diff could have given them a better top speed.
>
> Anthony.
>
> the whole report is still available and tagged at the 1959-68 web page.
>
This archive was generated by hypermail 2b30 : Tue Sep 05 2000 - 10:00:34 CDT