The 1500 was a great car--small on the outside, big inside, fast with good handling. By the time it got into production several years had gone by since its initial showing. The 1600 was essentially the same car--four doors, four cylinders--but with more power. Also, some of the things now considered basic (covered dash and carpets) began to become standard or at least mandatory options. The 1500 after all came with a metal dash and rubber covered floors.