A good pipe will give you a good increase in power, but not nessesarilary speed, you will have to change sprockets or tyre diameter to gain the speed.
If you get a pipe, unifilter, airbox lid off and a +4 timing advance, and re jet for the mods, you should be able to worry that Warrior a little bit.
If you can do, or can get a port job done, you should be able to worry it a lot.