Hi, I'm wanting to get a new Cat. looking into universal with 1 02boss in it. needing to know what dimensions the pipe is?? Im going to cut as close to the OE cat as possible and use clamps and reuse downstream 02 sensor. is the pipe 2 and 1/4 before and after CAT? Please help. I'm sure with 233k that CAT is FU**ed....

 

A way to tell if it's clogged is, at night, drive it fairly hard for 10-15 mins and as soon as you're done driving, see if it's glowing. If it's glowing, it's clogged. You're exhaust will have a bad smell to it if it's getting clogged.