New Cat Installed - Discoloration normal?

1993 Cherokee Country w/144,000 miles, 4.0L HO, AW4, NP231, D30HP, C8.25

I just installed a new Magnaflow/Car-Sound direct-fit cat (#23221). It appears to have stainless inlet/outlet pipes. After getting it up to operating temp, the pipes have become discolored. Is this normal? I assume it is just because of heat, but want to make sure its not getting TOO hot.

Thanks.

those things get extremely hot. i'm pretty certain that near the openings, my carsound universal cat has some gold to black discoloration. the stock exhaust on most XJs from my understanding is stainless steel and as such is less likely to change color, but i wouldn't worry too much about it as long as she's running well. i don't have any problems with emissions despite having the symptoms you describe happening.