With the 911 Dakar under development, Porsche set out to reestablish its offroad bona fides by climbing the highest volcano in the world — the Ojos del Salado in Chile. Porsche built two highly-modified 911 Carrera 4S coupes for the adventure, with one exception: Both cars have factory-spec turbocharged flat-sixes, the same as the road-going 4S. The prototypes are equipped with roll cages, carbon fiber seats, and harnesses. Portal axles were added for increased ground clearance and lower gear ratios for creeping over the harsh terrain, along with Aramid fiber underbody armor to protect the driveline. The Porsche Warp-Connecter mechanically links all four wheels to provide constant load to the wheels regardless of suspension articulation, backed by manually-controlled differentials. The result was a success, with the cars climbing over 19,000 feet in temperatures of nearly 86 degrees below freezing.