White Bros. E series Without end cap

Anyone running the white bros. e series slip-on without the end cap on a 400ex?

If so how much performance differance and louder?

Don't do it! It sounds horrible! just tried it (its Like having a beer can for a pipe).
I learned something here that I would like to share.
The sound that I was trying to get rid of got exaggerated when I eliminated the end cap. So with this theory I decided to eliminate some disc (2). The sound got a little better BUT I found it has more bottom end torque now! (way noticable) I love low end torque, yes I realize I will probably lose some top end as well, so be it.
If your running with the std 12 disc and like the low end torque than you may want to experiment as well.

[400exRacerX]

I have been riding without the end cap for almost a year now and love it. Its alittle loud but sounds great on my bike. I did notice alot of power gains in the higher revs.

[Smoker]

Did you jet your carb any differently when you took off the cap?

yea, mine feels better wit the spark aresstor out to, and sounds so much better, like harley

Dont know what to make of it? Why yours would sound good and mine like crap. Maybe I have a bad pipe? The crapy sound comes on let - up only, talked to white bros. yesturday and they said send it back and they will fix it if required free. But I dont want to send back if it aint the pipe. The crapy sound I believe is related to the disc.

When you guys eliminated your end cap did you also dump the disc?