The SLC soon became a rally favourite, winning the 30,000km South AmericanRally, along with many others. Around this time, competition was hotting up andthe race for new technology to deliver a winning edge was on and Mercedes cameup trumps developing a new lightweight alloy engine block, with out metalcylinders. However FIA rules insisted that all cars entered for rallies must beavailable to the public, with a minimum quantity of 500 sold being the basicrequirement. Consequently the 450 SLC 5.0 was debuted at the 1977 Frankfurt AutoShow. The new alloy engine allowed the SLC to weigh in at less than the shorterSL, quite an achievement. Some referred to this new vehicle as Mercedes' answerto the Porsche 928, and a year later, the SLC proved that it was just thatcapturing the first four places in the 5,600 Bandama Rally. For pictures and videos feel free to visit: In 1980 the 350 was replaced by the 380SL with a new alloy engine, which thanksto its weight difference resulted in greater efficiencies. The other markedimprovement was the additional gear; the SL was now fitted with a four speedautomatic box. However, the 380SL did suffer at the hands of a single timingchain at a time when competitors were turning to rubber, the single chain wasknown to either stretch, or loose performance, or worse, snap and destroy halfyour engine. Later models were supplied with dual chains, and many wereretrofitted. The 380 produced 218bhp and 224lb/ft while the new alloy 500SL(replacing the 450) managed 240bhp and 297lb/ft.