ungrades for a 98 cav

my gf has a auto 1998 cav 2.2l i have the exhust, intake, kombat body kit altezza's, clear cornors, tint. now i want to add more proformance parts to make it quicker i read that new pullies help but which brand and where can i get them all what other parts can i get to make her car faster thanks also if i wanted to put a more powerful motor in it what motors would you all suggest?