On my rhino I have stock double header pipes at 1" each, this means 2" of exhaust flow. The outlet on my muffler is 1",.. you do the math,....
So I installed a stainless 2" 45deg downturn tip,.. deeper, throatier sound,.. not so tinny now. I also have a twinair foam filter with bel-ray filter oil,..
Reason for the downturn is it's easier to keep water expelled when the back is under water, and my exhaust doesn't burn my box when the bed is tilted open.