i'm not exactly sure what's legal in California thanks to all of your lovely CARB certifications and emissions testing. Most people boost their cars and put them back to stock before they go get tested....its a lot of work, but it saves you having to buy an overpriced crappy kit that doesn't make that much power simply for the CARB sticker that goes with it. If you're interested in getting started, i have some parts that will help you out....here's one of them.
http://www.automotiveforums.com/vbul...d.php?t=563698
If you're serious about boosting your car, then let me know and i'll help you out. After building myself a kit from scratch, i have a pretty good idea of where to get things and how to get them cheaply. Building it yourself is a lot more rewarding in the end too...you can tailor your set up to be perfect for your car, your driving style and what you're going to use it for...