Despite the runaway success of Porsche's Cayenne SUV, big boss VWAG CEO Martin Winterkorn has admitted a smaller version is in the pipeline.Winterkorn said in an interview with Germany’s Der Spiegel that the smaller brother to Cayenne could be called Cajun. The Cayenne shares a platform with the Volkswagen Touareg and Audi Q7 and a small SUV based on the Audi Q5 platform makes sense. Volkswagen has plans to expand the Porsche range to boost sales. According to Automotive News, Winterkorn wants the sports car maker's sales to double to 150 000 units. A smaller sports car to slot beneath the Boxster and Cayman models is also being considered, it is reported.