Any difference with CA Metros?

[blowncopcar]

Sorry if this has been asked but I cant find it... My 97 3/5 Metro is from California and I'm wondering if there is a huge performance difference between the Cali and non-cali models? All I can tell is there an extra catalytic converter but is there any other things? And would there be any improvement in replacing the cat or anything else with non-cali parts? looking for any little improvement I can.... Thanks guys.

[MetroMPG]

Time delayed response...

If there were a significant difference, there would be a different set of California fuel economy numbers between CA & non-CA cars (like there were for the Civic VX for example).

[blowncopcar]

Thanks! I was going to replace the o2 sensor... I got a standard motor products upstream sensor for really cheap so I was just wondering if I replaced the manifold while I was at it if it would be worth the 60 bucks for the manifold and worth my time (which is really cheap lol)?