> A lot of Americans take their cat off on purpose for louder noises.

Some people remove catalytic converters when they install a performance exhaust. Nobody is doing it for louder noises because the muffler portion is what dampens the sound.

Also I wouldn’t say it’s “a lot of Americans”. We have emissions inspections in most major cities and your car won’t pass if you remove the catalytic converter. They can now detect modified ECUs, too. Someone would have to be so determined to do this that they’d swap the exhaust in and out every time they had to do emissions inspections.