What can u add 2 an 03 Taurus 2 give it more HP(i kno not a popular car N the race world except the Taurus SHO?

There is this car that always tries to race me i know the cars have about the same hp but the only thing is his car is a little lighter which makes it quicker...my car is custom looks wise... its all black with tinted widows 18 inch rims racing muffler and pioneer subs but i need more speed...