X Pipe or No?

[wmhjr]

There are a bunch of resources out there that show that X-Pipes are better than open headers. The X-Pipe assists with evacuation, as well as some other funky pulse effects.

As usual, I'll fall back to my bike building stuff where air cooled v-twin motors can REALLY demonstrate how different changes effect performance. The absolute best performing exhaust on one is NOT "Drag Pipes" or "true duals". It is almost always without exception a well thought out 2-1 stepped design. Open headers have one performance range - WOT. Assuming the combo is even tuned for that.