4.6 97 couger, , had a clogged catalytic converter I cut off , runs worse

What is your question?

Cut the right side cat off and welded a 45 degree exhaust pipe in and now it runs worse , I had two codes for o2 sensors bank 1 , replaced the down stream , up steam was replaced about 3 years ago so didn't do that one , there's a lot of pinging when I first take off but once it hits 3500 rpm it takes off and runs great, when I had the right side exhaust open I started the car the see and here how it sounded , it had Good throdle response just loud , but once the pipe was on it changed