Yet another newbie question: My 96 Zetec has a factory rating of 120 hp. The Focus as a rating of 130. Can someone explain the difference, if both are 2.0 liter Zetecs?

96 GL-Sport 2.0L, MTX Bernardo Bourges' CTA CAI, Dmitri's SVT E0s rims, 205/55R-16, Dunlop SPs.