Jotting down notes about what to do about the car after I get sufficient track and autocross (AX) experience. I'm planning on sticking with the rear engine platform for the near future -- sorry mid-engine friends! Mostly basing my trajectory on that of my friend edmack:
0. Brake fluid
I'm going to Thunderhill raceway in a couple of weeks and Willows, CA is going to be extremely (perhaps unbearably warm), so high temperature brake fluid will probably be good.
N.B. What happens if your brake fluid is rated at too low of a temperature? After sufficient runs, your brake fluid will start to boil and then your brakes will not work, as in pressing or stomping on the pedal does nothing.
1. Brake pads
Probably Pagids. I hear this name frequently, if only from personal recommendations and the Panorama advertisements.
2. Big brake kit
Since I plan on sticking with 18" rims, mostly for the sake of cheaper tires, I can use at most 355mm front rotors (though I think I need to check the clearance of the caliper with the inside of the rim) and something smaller in the rear (maybe 332s?), if at all. Also I plan on using slotted rotors as opposed to drilled to decrease the chance of cracking.
My current brake pads are still barely worn (I'm pretty sure they're 8 years old!!!) so I might be able to get enough track experience to get the BBK with the upgraded pads; one must replace pads and rotors simultaneously.
Will probably go with Michelin Pilot Sport Cup 2s for street comfort, longevity, and performance. I plan on keeping the car street-legal for the near future.
I'm new to various suspension geometries and parameters so will need to do a lot of research. I hear that the 911 (rear engine) platform tends to understeer because physics. Most of the weight is at the rear, so entering turns at sufficiently high speeds will cause the car to understeer.
Now I'm just kidding myself (until I get a garage and more disposable income)!!!
As always, tips, tricks, and anecdotes are welcome!