A method of improving the reflectivity of a surface of an internal combustion engine, the internal combustion engine having a cylindrical or non-cylindrical internal wall of an internal combustion chamber in which one or more pistons move and in which combustion occurs, the method comprising polishing a surface of the internal combustion chamber, said surface during use of the internal combustion engine exposed to combustion, said polishing effective to increase a reflectivity of the surface. The surface may include a first zone not traversed by the one or more pistons and polished in a first manner (pressure, time, electrical current density or voltage) to yield a first reflectivity and a second zone traversed by the one or more pistons polished in a different manner and yielding a second reflectivity.