A crank girdle is a piece that bolts to the bottom of your engine block that basically ties the bottom of the engine together to help combat flex and make the block stiffer. I didn't know that the first gen B16a's didn't have them, but then again, I've never torn one apart either. Definately a good thing to have, especially with a high rpm motor.

As for california issues, I would recommend you contact the place you'll take your car for it's inspection to get the most honest answers. Some say people online say "no JDM engines!" and other say it's cool as long as you have all the smog equipment. I'd get it straight from the horses mouth. Seeya.