Be careful, I bought an aftermarket one on line years ago, and the flange bolt pattern was wrong. I ended up slotting the holes to fit the bigger pattern on the 1700 head. On the 1600, I just cut off the pipe just below the muffler and picked up a TSC muffler and rain cap. Put a U-clamp on it, and never had an issue. The OEM flanges and pipe is heavy duty, so it will last a lot longer than the mufflers.