Actually that's the wrong dyno sheet, which is why they all say stock at the top. IIRC Alex had a bad coolant temp sensor which was causing the funky powerband.
This is the dyno RBS14 meant to show you: first run is completely stock with a cold air intake, second run is with the addition of a 3" exhaust.
Don't worry about smog, exhausts aren't smog devices. If you have vehicle inspections though you need to see if giant cannon exhausts are legal.