So far my car is completely stock and I have been thinking of getting an intake and/or exhaust ($ is low at the moment) for my GS-R. An important factor I'm looking aside from the power and sound, is for is the carb legal or smog legality of the parts. Can you guys give me suggestions of what products are good and also have a certificate that it comes with that shows proof?

So far I am close to making a decision on the intake, AEM Short RAM and Weapon R (Dragon or Hyper). The HKS doesn't seem to be smog legal right?