no hp or like .0002hp just removes weight and cleans things up under the hood a bunch, plus if you are in a no emmison state and have no cats the air pump is just along for the ride, however if you still have cats you HAVE TO KEEP the pump or the cats will clog and that is no good, removing it will also cause you fail a visual emmisons inspection If yo decided to remove it search the tech section there are several good threads