Coming back from the engine you have the Exhuast manifold which runs to the cat, then the cat runs to your muffler. If you remove the cat, the car will sound MUCH louder and probably feel more powerful as well, however, it is ILLEGAL to do so since it's emissions equipment. The next thing you can remove is the muffler. Since the cat already acts as a muffler, you'll probably be under the legal noise limit. That's why I said it's probably legal to remove the muffler and instead run a pipe from the cat all the way to the back of the car (deletes muffler).
The straight pipe wasn't meant in a literal sense.
[OT] Isn't your computer water-cooled? Check for a leak at the CPU WB. I killed an AIW 9800 Pro because my WW dripped coolant all over the card
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