I don't mean to be a wet blanket here but...Question that has to be asked: if you are going to (like so many people your age) dump so much money into your slow car to make it go fast(er), why didn't you just save up and by a fast car sometime later. Those modifications and additions given by the posters above are going to cost you 1000's of dollars in parts and labour...

My suggestion: you made a good choice buying a reliable car for next to nothing. Save up for a couple of years and avoid dumping money into your car. By the time you're ready for college (or nearly finished college) you'll be able to get a car that is very capable in its stock form, and a bit newer.