Originally Posted by A Y
I wouldn't worry too much about getting a really fancy car initially. If you want a track toy, then get one, but there are lots of perfectly fine cars that can handle track duties with little problem, especially as you're starting out.
For example, an E36 M3 restored to factory condition for its suspension and bushings will be enough car to take you all the way through any school's advanced run group. And it's always great to have a comfy car and AC for the drive home after a long day at the track, and it's nice to have enough storage space for hauling all your track paraphernalia.
+1. Most decent street cars cannot be driven to their potential by the typical HPDE student. A powerful sports car just gives an inexperienced driver more rope with which to hang himself.
You will go through many sets of brake pads, rotors, brake fluid, and tires. Factor that in because while those 19-inch 325-width tires look really cool, they will cost you an arm and a leg when you have to replace them. That is, if you can find the tire you like for them.
This won't happen until you're well into the intermediate or advanced run groups. You have to be either really bad (locking up tires and unnecessary wheel-spin in every corner) or pretty fast before you're eating up too many tires and brakes. Or driving a really heavy car.
Most groups are pretty marque-agnostic. The BMW CCA will let any kind of car run in the driving schools, for example. Do research on the schools near you, and find one that's relatively conservative. There are some pretty bad groups out there that don't teach much, and have pretty bad safety practices. You want a school with instructors in the car with you and with full corner workers stationed, with emergency vehicles standing by. You can also look to see how many people they send on to racing school successfully as another indicator of their teaching efficacy.
There's really no need to go to a Lotus school if you have a Lotus. For the most part, car dynamics are the same across different cars and drivetrains (RWD, FWD, AWD), as you'll adjust your technique a bit for different cars. They should all teach you the same thing that you can apply to any car: the tools to cause a certain action as well as the sensitivity to know when and how to deploy those tools.
Another good point. Last time I checked, the Porsche Club wanted the VIN of your Porsche on the membership application.
Has anyone mentioned that most HPDE's pair you up with an instructor and have required classroom sessions? Your enjoyment of the event will depend significantly on the quality of both.
Also, you will likely find it very addicting.