Relish this number: $22,191, that's Porsche's net profit per vehicle. No other carmaker in the world comes close to such amazing margins. Porsche, however, is ambitiously seeking even greater returns. It plans to do so despite increased costs, chiefly due to manpower (employment has increased from 12,000 to 18,000 in the last five years); infrastructure (the Weissach think tank is currently undergoing a major expansion); production (the factories at Leipzig and Zuffenhausen in particular need to be brought up to speed); marketing (Porsche experience centers are mushrooming globally); and distribution (Korea, Russia, and Brazil require instant attention). Slow start for the 918 This fall, Porsche will roll out the mega-complex and mega-expensive, limited edition 918 Spyder. While the competing LaFerrari sold out instantly (and will be followed by a run of 500 drop-tops as well as by about 200 hardcore FXX variants in 2015 and 2016), the plug-in supercar from Stuttgart is still a