Innocent friend with a cavi

So my best friend asked me to help her make her cav. 'fast'. it's in great condition and let me tell you we beat the piss out of that thing, so why not make it fast as well.
Any Ideas on what to swap or instal.
Get back to me
oh yeah, and does anyone know how to fix key marks? her car got keyed and we bought the 'scratch fix' shit... ha ha dont' even try it...