Here is what i found out my buddy has modified banshee and i have a modified 400ex from a dead stop on a dirt road i kill him out of the hole but once he gets into 5th gear he's next to me then 6th and he's gone i wish that i had one more gear. pretty much the same on pavement to but i get beat a litte bit worse. y2k 400ex DMC exhaust K&N air filter kit with outerwear no airbox lid