yes the CEL does come on for most people because the cat is high-flow. you have 3 or 4 options for the CEL, which should be a P0420 code.

1. Get the code tuned out (97-07 years only)
2. Get an o2 emulator (97-03 years only)
3. Use the anti-fouler mod
4. Don't give a rat's ass and just keep driving