I noticed recently that the K&N Aircharger part #63-1032 does not work with the SC version Xterra. Then as I searched further into the K&N site, I discoverd that the Frontier uses the same part #63-1032 and also has a Supercharger version part #63-1052. Well, being the logical kind of guy I am, I figured if the 63-1032 works on both the X and Frontier, and the Frontier has a SC version in part #63-1052 then that one should work on the X.

K&N wrote back to me saying:
Our kits are application specific and emissions legal so they do not cross over to other years or models. Our R&D Department is in the process of testing this kit for kit and performance.

Huh? Do not cross over? What about the 63-1032? It seems to "cross over".

I guess I will just wait until they figure it out, or some other company impresses me first.

I've had kit #63-1032 installed for six months on my XE-S/C. It works just fine. The only problem is CARB approval. None of the Aircharger line have CARB approval. I don't have to worry about inspections, but seeing that you are in CA you'll have to wait for the FIPK version to become available.

Looking at the #63-1052 the heat shield is redesigned. It looks like it may have fewer and smaller gaps to allow hot air past. I would think it would fit an S/C Xterra.