I need to replace the seal from the headers at the catalytic convertor. While I'm at it, I will replace the catalytic convertor. The current cat has a pipe coming from the side, it has been welded shut. Is there a hose that should go there? The replacements show some with and without that pipe. If it should have a hose, where does it go?

 

why replace the cat ?? is it bad? the tube on the side is an air tube that you dont need it just means the cat you have is universal aftermarket already you should look into your local smog laws here in ca the numbers on the cat have to match for your vehicle otherwise it will fail the visual inspection and if you keep going through cats it probably means something is wrong with your motor making them go bad

 

I have to replace the seal from the header down pipe to the cat. I was told that when in doubt replace the cat. I will be under there working for several hours because the clamp/bolts for the seal clamp are broken. I was going to punch through the cat but have decided not to. It is the law, plus I want a nice environment for my kids in the future.