The S600, launched in March of 1964, was the first Honda car to be offered in two versions; a convertible almost identical to its S500 sibling, and a fastback coupe, introduced in March of 1965. Styling would remain pretty much the same, with the most noteworthy changes coming to the front grille, bumper, and headlights. For this model, the engine capacity was increased to 606 cc. The engine produced 57 hp at 8,500 rpm and had a top speed of 90 mph. With the convertible weighing in at 1576 pounds, the extra sheet metal of the coupe only added 33 pounds to the overall weight. The S600 was the first "mass marketed" Honda car. First offered with right hand steering only, it soon became available in left hand steering so as to be appealing to the export market. (There were a few pre-production S500s manufactured with left hand steering, two or three even being shown in some early sales brochures, but all production S500s were right hand drive.) Both the S600 roadster and coupe were available in standard trim and a special, upgraded package called the SM600 which included, among other items, special paint colors, exclusive badging, a standard radio and speaker, a special antenna in the passenger side sun visor, standard reversing lights, a standard cigarette lighter, a standard heater, better cushioned seats, and a detachable seat track for quick removal of the passenger seat. Production of the S600 was much greater than that of the S500. In fact, of the three production engine sizes for the sports cars, the S600 had the highest figures. Honda built 3,912 roadsters in 1964, with production climbing to 7,261 convertibles and 1,519 coupes in 1965. Production dropped off in 1966 (as they were shifting to the S800) with only 111 roadsters and 281 coupes, giving tallies of 11,284 convertibles and 1,800 coupes for the 3 year span.