i think a blaster with stock pipe, tires and gears will do somewhere in the neighborhood of 63 mph.
if you put an aftermarket pipe on, it, in fact, can increase top speed b/c the pipe can increase over-rev. ie. a blaster with a stock pipe might only be able to turn say 7 grand while a piped blaster might turn 8 grand. not gonna amount in a lot of speed, but it will be some.
tire size as well as gearing will affect top speed and acceleration.
oh, and so will that extra 50 lbs you have hangin off ur gut.