[jwade]

You have some options.

1. If sound is what you want, get an OEM Porsche Sport Exhaust. They sound great! I have the version 1 on my '01 S and I love it! I don't know what year you have, but the PSE will set you back around $2000.

2. You can purchase NHP (Maxspeed Motorsports) headers and bypass pipes to stay CA legal. These two alone will set you back $1300 if you keep your current muffler and I would expect some performance gains from this system.

3. Go high end and get the Fabspeed system. It's really nice, but headers and bypass pipes alone will set you back $3000 or so if you retain your stock muffler.

4. Do either 2 and 3 above with replacing your muffler and you will be another $1500 in the hole on top of the prices mentioned above.

5. If you don't care about getting a CEL, get Turbowerx headers and some fabspeed bypass pipes along with a Dansk sport exhaust. You will spend some money here, but will add power there for sure. As far as smog legal, you WILL NOT BE, so you better retain all your stock stuff and be ready to have it put back on prior to being inspected.