I would be very careful about using one on a non-controlled car. They are designed to 'burn' exhaust gasses thru catalytic action. Yopu don't want to just throw one on behind something with a lopy cam for instance. They are also not the best flowing unit, and there are plenty of mufflers that flow better and are designed to quiet the sound.

The SRT 4 only had the turbo, a cat and a resonator for sound, no muffler.