If you haven't already downloaded Elvo's site then do so.
http://home.tiscali.be/be067749/58/
Experiment a bit more while you are at the track and you will answer many of you questions regarding actions/desired effect. This is the only way you will answer some of the questions you posed above due to many of the reasons Data listed among others.
Maybe it would be more beneficial if you post in the thread applicable to your car so that you will get help from people who actually run the same car as you do and therefore have real experience rather then the theoretical type. (you have so many in your sig)
Have fun !