Back in May, not long after I got my car and before I'd learnt much about the
PCA track & AX events, I booked a
High Performance School slot with Jim Russell Racing at Sears Point. It was one of the few commercial schools I could find that let you get your own car on the track, and I'd been to enough races at Sears Point to want to have a drive there. It rolled around earlier this week, and so off I went with
my new camera mount (and old camera). Here's an edit of 3 or so laps, the video is just OK but the sound is pretty good and the old CS sounds very sweet. I kept the bitrate modest so the video should sort of stream over my server's T1 connection...
Windows Media @ 1mb/s (57MB):
http://www.lyric.com/downloads/qzxxc...-sears-1mb.wmv
Quicktime 7 @ 1mb/s (55MB):
http://www.lyric.com/downloads/qzxxcayman65y/cayman-sears-H264-1mb.mov[/quote]
There were about a dozen cars, including Porsche C4s, C2 cabs, RX-8s, a Z4-M roadster, an Audi S8, my Cayman S and a Ferrari 360 Spider. All the drivers were new to tracking. For the track sessions, the cars were paired up based on expected speed and, of course, the Cayman was matched with the Ferrari!! There was one instructor per pair and he was always in the lead car to keep things under control. Most of the video shows me following the Ferrari and actually getting a bit pissed at having to slow down all the time. The driver seemed to have a hard time finding the apexes. The last segment shows the instructor driving me around, talking through the line.
I got up to around 100mph coming up to turns 7 & 1 but they had a speed limit of 65mph through 8 & 8a (the downhill esses) to keep you on the track and away from the concrete there. I'm certainly no expert, but at no time did the Cayman feel unsorted, it was very easy to drive and felt controlled even when we did get into a couple of throttle drifts and even an inside rear wheel spin (now I know why everyone is complaining about lack of
LSD).
It was the first Cayman they'd had attending the course, and the instructors (and other drivers) were all very attentive and complimentary. My instructor seemed very impressed, said it was a lot tighter than the Boxsters he'd driven and apparently told the Ferrari driver it cornered better than his 360.
To be honest, the course was a little dissappointing. The morning skid-pad & emergency maneuver exercises were a bit perfunctory and the two 40 minute afternoon sessions on the track included a lot of lining up behind slower cars. To be fair, they controlled the safety aspects extremely well and kept drivers in their comfort zones and the instructors were very, very good. It's definitely a good course if, say, you don't know what a late apex is, but even with just 3 autocrosses under my belt it was a bit frustrating.
Anyway, I'm off to ButtonWillow for my first
PCA-GGR DE the weekend after next and hope to have some more video then. With luck I'll have convinced the trouble-and-strife that I should upgrade to one of the Sony HD camcorders you chaps are using to such great effect.
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LSD - Limited Slip Differential
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A limited slip differential (LSD) is a modified or derived type of differential gear arrangement that allows for some difference in rotational velocity of the output shafts, but does not allow the difference in speed to increase beyond a preset amount. In an automobile, such limited slip differentials are sometimes used in place of a standard differential, where they convey certain dynamic advantages, at the expense of greater complexity.
The main advantage of a limited slip differential is found by considering the case of a standard (or "open") differential where one wheel has no contact with the ground at all. In such a case, the contacting wheel will remain stationary, and the non-contacting wheel will rotate freely– the torque transmitted will be equal at both wheels, but will not exceed the threshold of torque needed to move the vehicle, thus the vehicle will remain stationary. In everyday use on typical roads, such a situation is very unlikely, and so a normal differential suffices. For more demanding use however, such as driving off-road, or for high performance vehicles, such a state of affairs is undesirable, and the LSD can be employed to deal with it. By limiting the velocity difference between a pair of driven wheels, useful torque can be transmitted as long as there is some friction available on at least one of the wheels.
To see the installation of a LSD style unit Click Here -> Article Forthcoming Stay Tuned |
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Linear Mode
