How can i convince my parents into letting me buy a porsche as my first car?

I will be turning 16 i a little under 3 months. I've had my permit and have shown my parents that i drive safely. I have been looking at older (1982-2000) porsches craigslist and seen that at prices i can buy with my own money ($1000-5000). I can also afford the insurance. I've had a summer job for 3 years and have been saving my money for a cool car. My parents wont even talk about me buying one. They think that I am going to crash it or something. Could someone please give me some ideas?