Originally Posted by FrankThomas
You need to cut the stock X-pipe if you go with the Challenge Street. The primary cats remain and then a cut is made after to install the challenge which eliminates the second set of cats. The end of the challenge street will be compatible with the Dinan rear section.
Thanks! Not sure I'm keen on cutting into my stock pipe. I guess the only way to do this is to suck it up and go for a tune.