"M" > wrote in message
...
> So where does the x pipe fit in ? does it replace the "Cats" & is it
legal?
>
> Thanks

The catalytic converters are closer to the front of the vehicle and remain
in place when you put on a "cat-back" system.

An 'x' pipe is a cross-over between the two pipes closer to the middle of
the car, and behind the catalytic converters many times for sound