just curious... I am not necessarily debating hollowing it out, but just wondered what the restriction will do to the performance?

valve stems/seals leaking oil is why the cat is cooked if it matters..

 

Id like to see some responses too. i had to hollow out my cat today. the insides were completely shot. it ruined my o2 sensors. im wondering if i should roll like that too or replace it. my ride seems to be running even better.

 

I got a Direct Fit Magnaflow Cat that's flanged and bolts right up, cost about $85. That was much easier than buying a universal one, and then having to buy a flex pipe and have it all welded, I'm guessing that route would cost more.

You can hollow it out but it might not sound that great and don't expect to feel any gains, you might lose torque too. Plus it might smell funny to those driving behind you.

It's proven that replacing the cat for a test pipe can add horsepower, but I'm not so sure about a hollow cat. It just doesn't seem worth it to me. My 2¢.