I have owned my 99.5 a4 since june and have done nothing to it except rims and tires. I have many questions that I will have to research on here and I will prob find the answer. I live in the temecula area of southern calif. my car has 163k miles on it what could I do performance wise if any to it. If anyone can point me im the direction I should read up on let me know I know very little about my car thank you