I have 06 LSV.. What ballast bags do you have?
Did I understand your post to say you had both left/right bags filled? If so, you only want to fill the side you plan on surfing. I have upgraded bags in mine and have 750's in the rear, so when I fill center and one side, i get a decent wave. If we have 4 or more people in the boat it is much better. A person up front will help lengthen the wave as well.
If you have not yet, join us over at the moomba.com message board. We have recently added a wakesurfing forum and there are a couple of folks who can really help.
Assuming you have the stock 400lb bags in rear lockers, you will need a few more people on the surf side. Also, wakeplate between 75-100% up.
We rode today at 9.8mph and had good wave..between 9.8-10.3 seems to be pretty good for us...
Enjoy the boat!