What's the difference between H, X, and dual exhaust with no h or x between the pipes?

 

Im running a dual exhaust with flowmaster 40's 2.5" tubing i think the H pip crossover equalizes both sides of the engine giving it a bigger torque curve oh and it takes care of back rap on deceleratoin something glasspacks wont give you.

 

Oh ok

I was just wondering what X/H's had over plain dual exhaust

 

The cross pipe, be it H or X, balances the exhaust pressure between both cylinder banks. They've been proven to give mild power increases (5-10hp), but they also mellow out the exhaust tone, making it less raspy and poppy. Personally, I prefer the sound of an H-pipe exhaust on an OHV engine. X-pipes just sound funky to me.