Yeah it ran better. Sound isn't that much different from stock but a bit more loud. And yes you'll get a cel

 

Trex87 you were right, must have been a crack as last week it clogged, when I took it down the front honeycome bits where in pieces and the rear one clogged with its remains. Luckily the boy didn't drive it long to get it home, maybe 10 miles, the air pump under teh hood making all kinds of noise. Hollowed it out, man if there the stuff in these!! It now runs like it did except for sweet smelling exhaust its now pretty stinky. I think what killed the cat is I did the blue washer fluid decarb process, maybe a bit too agresively as I got the cat pretty hot once. While car was up on jack stand I did another compression test to mainly see if running it with blocked cat hurt it and also to see if compression increased from the decarb but found it to be exactly the same as when done about 2000 miles ago, a good thing in the cat clog didn't appear to do any engine damage the bad thing the decarb process did nothing except ruin my cat.

 

Glad you got it figured out, the cats on these cars can be very tricky.