I want to take the single cat of my car. I dont want to gut it, i want to take it off, what single inexpensive mod can i don which i can take cat off. headers? catback? y-pipe? someone told me i need a custom pipe to replace cat?

More than likely you would need a "custom" piece to replace the space left by your cat. Most aftermarket exaust systems go from the cat back, not from the y-pipe back.

The cat should slip on to the stock y-pipe. Be warned that more than likely the cat is siezed and will not slip off.

A muffler shop that overlooks the $5000 or so fine for removing your cat shouldn't mind hooking you up with a replacement pipe. Be ready to hear the word NO though.