California Emissions Cat vs standard

[Rip5757]

What is the difference between a California Emissions compliant catalytic converter and the Federal Emissions compliant converter. I'm afraid my '01 Impala has the California Emissions and I need a new converter. Car has 150,000 miles on it so the extended warranty is out. I can get a direct fit Federal converter for under $200, the California compliant is over $1000. Will the direct fit Federal one fit into the California spot?

[Rip5757]

Just wanted to give an update. The cat continued to worsen and just couldn't pull the hills in Vermont anymore. I bought a non-California Maremont universal fit cat for $59. The plan was to cut out the old cat and clamp the new one in. Unfortunately, there was a sharp bend in the pipe right before the cat and there was no way to get an adapter on there. Brought it to my local shop and he had to do a bit of fitting but got it in. The check engine light has not come on so I guess the O2 sensor is happy. I'll find out in about 22 months if the emission levels are OK.

[richtazz]

In case anyone else looks at this thread, I show no difference between California and non-california converters. It does matter which engine you have, as all 3 available engines use different converter part numbers.
3.1-J is GM part #12563200
3.4-E is GM part # 10343185 California NC1 or Federal NF4/NF7
3.8-k is GM part #10343187 California NC8 or Federal NF7

Also, GM extended the Converter warranty on GM W-bodies for the 01-02 model year to 120k miles due to a known issue with the factory converters, so before you pay to have your converter replaced on these cars, check with your dealer to see if you qualify for a free replacement from GM.