generally provide for forming ribs 141 as this type of geometry may not be formed using conventional stampings with reference to fig5 and 6 an alternate valve plate assembly 216 may include first and second valve plates 218 220 first valve plate 218 may include generally planar first and second surfaces 222 224 having a series of suction inlet passages 226 suction outlet passages 228 and bolt holes 230 passing therethrough second valve plate 220 may include first and second surfaces 232 234 having discharge passages 236 and bolt holes 238 extending therethrough and spacers 240 extending therefrom it is understood that spacers 240 may also include ribs not shown as discussed above first surface 232 may include a recessed central portion 242 having a wall 244 extending therearound wall 244 may include first and second portions 246 248 second portion 248 may be disposed radially outwardly of first portion 246 and may extend axially outwardly therefrom a distance generally equal to the thickness of first valve plate 218 first valve plate 218 may be formed from a stamping process and may be made of steel second valve plate 220 may be formed by investment casting and may also be made from steel similar to second valve plate 20 however rather than being.