An apparatus for and a method of prepping a surface of a cylinder bore using a pulsed waterjet entails generating a signal having a frequency f using a signal generator, applying the signal to generate a pulsed waterjet through an exit orifice of a nozzle having an exit orifice diameter d and a length L. The pulsed waterjet prepares the surface to within a predetermined range of surface roughness. The surface roughness is determined by selecting operating parameters comprising a standoff distance (SD), a traverse velocity VTR of the nozzle, a water pressure P, a water flow rate Q, a length-to-diameter (L/d) ratio, the frequency f, and an amplitude A of the signal.