I did the Morgan Aero Racing Stage 1 route with S&S Stealth high flow filter and shorter less restricted Morgan Aero exhausts. M3W ran fine but didn’t like the sound of the exhaust. Eventually drilled out the front baffles of the stock exhaust and reinstalled. Works as well and exhaust note much better. Left cats untouched. I do have the upgraded 569 cams and ECU remapped for those cams but feel you really don’t have to do that.
I highly recommend you simply drill out the front baffles of the stock exhaust and not install the G56 or Morgan Aero Racing exhausts and install a S&S high flow air filter with standard ECU. This works just as well as the Morgan Aero Racing and G56 Stage 1, exhaust note is great, and much easier and less expensive. You will be very happy!
There is an earlier thread that explains how to drill out the front baffles. I did it myself.
Best of luck.
I too might take off the AR Mufflers in favor of the drilled stock mufflers because the AR mufflers are pretty loud. I have already drilled the front baffles but just not installed them yet. I figure it is a good winter project to swap those pipes.
