Does anyone know if a 05 sti intake manifold fits a 03 wrx??? If it does, does it make any difference in performance than stock???

 

it will fit, however there wouldn't be any performance gains. And you would have change out your whole throttle linkage to a drive-by-wire system, which is too much of a headache to do. the reason why you can't keep the throttle linkage is because the wrx manifold is slightly different.

some subaru gurus can back me up on this.

 

Yes the 04+ STi manifold is drive by wire meaning there's no throttle cable, just a sensor on the peddal connected to an actuator at the throttle body. The 03 WRX will be a drive by cable system meaning not only would this have to be changed, so would the cruise control system if you'd want to keep it.