rldzhao,
How often do you organize these track days? My friend who is on this forum [Iceback aka Steve, Alpine White E90 M3, Canadian guy who you may have met at a recent lunch gtg] told me about these ad hoc days you organize. I've got an E46 M3 that I run in NASA TT and would love to plan for a shakedown test or two during one of your track days after all my track mods are complete before my next NASA event. I've got a target lap time at MSRH that I'm trying to hit and when I do I'll know that I've got a car capable of winning. I'm tired of finishing 3rd or 4th!
Let me know if this is a monthly thing, a summer thing or whenever the fancy strikes you thing. Would love to join you guys and check out your rides.