STUTTGART, Germany - Porsche is launching its most powerful diesel model yet - the Cayenne S. Powering the new model is 4.2 eight-cylinder biturbo engine capable of 281kW and (more importantly for a diesel) 850Nm. The engine rockets the SUV to 100km in 5.7sec and on to a top speed of 252km/h. Fuel consumption is rated at 8.3/100km with CO2 emissions at 218g/km. The new model uses the automaker's all-wheel drive with optional Porsche Torque Vectoring Plus (it sends the drive to the wheel(s) with the most grip.OPTIONAL 100-LITRE TANKThe Cayenne S diesel, the automaker believes, is ideal for towing and manoeuvring a boat or horse trailer with its maximum towing capacity of 3.5 metric tonnes.Buyers will have access to an optional 100-litre fuel tank which will, according to Porsche, allow the new model to cover 1200km.The exterior benifits from a number of extras over the standard model. The brakes have silver callipers and black fins at the front emphasise the air inlets.The Cayenne S diesel will be launched in January 2013 and will retail for €77 684 in Germany (R815 961). We're still waiting to hear if it will reach South Africa and, if so, what it will cost.