RCZ

1) Absolutely not, you will NEVER be able to get the temperature up past normal points while driving on the street. You do NOT need an oil cooler if you are going to keep it on the street.

2) I changed the brake fluid because the stock brake fluid is not designed to handle the temperatures created during track driving. Again, this is something you will never have to worry about on the street. As you know, when you hit the brakes, there is a lot of heat generated. When you are on the track, this heat doesn't have enough time to dissipate and therefore the braking system gets extremely hot. The stock fluid will boil at a much lower temperature than racing brake fluid does. If your fluid boils...it is very bad. Air in the braking system can cause brake failure, more often than not it will get so bad that it wont be safe to drive anymore. Racing brake fluid has a much higher boiling point and often even a different consistency than the original stock fluid. That means you can put it through its paces on the track without having to worry about it. I recommend RBF600, it isn't so expensive and it is very good. Currently I am running ATE Super Blue and it is pretty good as well, no complaints yet. However, it is about twice as expensive as the RBF600....$80 for two bottles...