On my Titan I liked the sound of the stock muffler but want the dual exhaust look. Therefore, I am considering having a "Y" pipe installed on the back side of the stock muffler, and running two 2.25" pipes out either side of the hitch and adding 3.5" chrome extensions. My questions are

, does anyone know if this will change the sound of the exhaust? Will performance be effected (for the better or worse) by adding another "Y" pipe on the back side of the muffler? Anything else to consider? Thanks.