I would pop the hood and see if there is a label under the hood restricting sale in California.
I'm certain the emission requirements dictate different tunes that would affect performance.
That's a certainty right there. CA has had tighter emissions standards for decades. I thought this was common knowledge within our community. Anyway, any new car destined for sale in CA has to meet their cleaner requirements. Since the market there is so big, having such a large population, car manufacturers actually save money by making only the cars going to CA with the more expensive emissions equipment. It's been that way for a long time now.
This will definitely tame power to make a cleaner burn in CA. There is no doubt in that regard. How much power and where in the RPM range that it is sacrificed is all that is in question here. I'm sure it's only a few HP and ft lbs but it would be interesting to know.