My first palne was a wing running a 400 brushed motor and 1800 mah nim battery, just barley enough power to fly the thing. Bought the 1.8kv Xtra brushedless motor at Hobby people when they had their yearly sale for $20.0. Now it flys around 80 mph yet still does not have unlimited vertical...almost though.
The 1.8kv brushedless motor coupled with the 1800 mah nim battery is about as fast as you can get using the nim battery pack, anything bigger i would need to go lipo. Most people around here use a max of 3 kv on their wings, and they fly so fast it pretty scarry at times. A friend of mine uses a "Mega" 3 kv on a 36" wing and its the fastest elec i have ever seen...