I want to remove my cat for track use and general jack ars type of behavior. My question is this. If I take the cat out and just knock the honeycomb crap out of there... Is that just as good as putting a straight pipe on there? Or is there some loss due to the shape of the cat's housing.

Appreciate the thoughts on this one.

...The cat can back on witout much trouble.

...Mine was registered as a collector car. I skater around an emissions test that way.

I live in California. Registered elsewhere. I have considered registering here but I know the testing thing is a pain. Perhaps collecor car would work. So really the issue is whether a peace officer would look under there and give me a hard time. Could it happen?

...Summit Racing sells them for something like $70.

I'd put a 3in shorty cat in there and keep the stocker you may need it. The current EPA laws dictate that the cat must be a direct replacement in "appearance and fitment and location" (thanks to your dealer network lobbying here), which means that someday the stock may be the only "acceptable" cat. Summit racing 3in high flow works (btdt). A hollow cat actually creates more turbulence than good. In theory and practice, you want the swirl flow out of the turbo tchanged to laminar flow the cat provides.

But if it's not registered there, then they may not be able to say anything. They could say you needed to register it there tho'.

Am I missing something on the Kalifornia reference? Does it have to do with the fact that we live in a Socialist/Police State?

Check out ebay. Item #1858644433 for a nice bolt on cat replacement.