In the case of the motor it is the rotor and the stator and for the pump it is the impeller and the volute (or diffuser). Of course the friction produced by bearings and other mechanical components (seals, stuffing box, etc) also affect pump efficiency, but the impeller and volute have the greatest influence. Lets start our investigation of centrifugal pump efficiency with the impeller.
The only difference between sport coats and blazers is that blazers are always solid-colored, usually blue, black, camel or dark green, while sport coats encompass about everything else. Blazers are considered more basic and more formal than sport coats. Photo Credit Jupiterimages/Brand X Pictures/Getty Images.
The difference is soley in options. I bought a 2002 Sport, only because the option I wanted was not available in the X. If it has what you want, buy it; there is no structural difference between an X and a Sahara, or Rubicon...just options. The Sport might have a tow package, which means a beefier rear end, if you offroad or tow stuff...but, that's about it.