cali has CARB, which makes it a ******* sh*tbox for modding cars. just look at the intakes - a CARB legal one (AEM, INJEN) is 250-300 bucks, but ones from weaponr or whoever is like 120. yeah, you pay for the brand to an extent, but you pay to have them test it for CARB too.
if you get an inspector who follows the rules and knows what a modded car looks like, just an intake can make you fail. intercooler can make you fail. midpipe can DEFINITELY make you fail. its all in who you end up with, and dont be surprised if you have to find less wholesome dealers (or methods) to get you to pass.