1999 S80 Has anyone straight piped a Volvo S80?

[Volvo S80]

Hi to all,
I have a Volvo S80 1999 2.4 non turbo i was thinking to remove the catalytic converter, people say it will increase horsepower and gas millage, since we don`t have any regulation about the emission and noise on my country I thought why not.
I don`t know if this will set the emission codes since it has an O2 sensor on catalytic converter if this will be fitted on straight pipe in the same location and will it be much louder because I think that it will not look good on a executive car like S 80?

[precopster]

You will get codes from O2 sensors unless handled extremely well.

Catalytic converters generally don't restrict flow. If you have a look at one in cross section you'll see that airflow is not impeded much. Mufflers are far more redtrictive.

[JDS60R]

There is more back pressure in your muffler than the cat. The non turbo cars also need a little back pressure to be efficient at low to mid rpm. If there is nothing wrong with it I would leave it alone.

[Volvo S80]

Thank you for your opinions, I will leave it as factory invented the car goes like a dream no problems and no codes .