Riley IMP BHY327 for sale with interesting and well documented history. Dr. D.G.Styles -historian and registrar in the Riley Register- state that only 1 prototype IMP, 10 racing IMP and 94 road going IMP have been manufactures in 1934 and 1935, this IMP with chassis 60-25512 manufactured as one of the first 30 cars in early 1934. Approx. 50 IMP ..