Moving a little off topic, but will help everyone none the less.
The first day (June 30) I was standing about 15m in from the apex of the corner, so not using the full length. Some are cropped a little as I was a little wider to allow for putting them in the wrong spot in frame as it really depended where I caught them coming into the corner
The second day was a mixture of 3 - 5m from the track so I wasn't using the TC at that stage, as well as using the full focal length for some of them with the TC. realistically I don't notice much difference with using it or not.
Using the 340mm effective length I was sitting out just inside the spectator fence, this would be about 25 - 30m I think from memory. These are cropped a bit more, a 400mm would be ideal for that style of shooting.
The software is Monokai's flash slideshow coupled with Gallery 2, there is coding in a custom gallery theme to pull the items from the gallery album and populate the xml file for Monokai's slideshow.
Cheers
Brett