I don't believe there is personally. I did mine and Wendys and all it did was change the exhaust note some. It split the sound up so you hear each pipe more than a blended sound. Made each cyl. have a more crisp pop when it fires and to me that was worth the effort but maybe not to others. I didn't notice any performance change either way although I didn't dyno it before and after.

I learned all I need to know about life by killing smart people and eating their brains.
Eat right ,Exercise ,Stay fit, Die Anyway!