Warehouseshopping; Inside Porsche's Motorsport Center.(Motorsport Center)(Company overview)

Byline: GARY WATKINS

Take a guess: What is the world's biggest race car manufacturer? A few years back, Reynard held that distinction, so maybe you'd plump for open-wheel car constructor Dallara these days. Or perhaps Panoz, which turns out Champ Cars, the odd IRL chassis, sports cars and junior open-wheelers from its U.S. and U.K. factories. Sorry, wrong answers. Porsche trumps them all.

Porsche's race car output is tiny compared with the number of street vehicles it builds, but its projected total of racers in 2007 outstrips any pretenders to the crown. It expects to build no fewer than 275 cars destined for the racetrack this season. That total includes seven RS Spyder LMP2 prototypes (one test car and six that will compete in the American Le Mans Series), 37 GT2-spec 911 GT3-RSRs and-wait for it-231 911 GT3 Cup cars for the world's 12 Porsche-only series, from the Formula One-supporting Supercup to the IMSA GT3 Cup Challenge in North America. That easily surpasses the 195 racers Porsche built for 2006.

The phenomenal growth of Porsche's race car business explains why it rebuilt and expanded what is now known as the Motorsport Center at its famed Weissach research and development headquarters near Stuttgart. "We were popping out of our seams,'' said Hartmut Kristen, head of Porsche Motorsport.

Redevelopment of the site, which technically should be referred to as Flacht because it lies closer to the village of that name than to the town of Weissach, started after the company board approved the expansion in February 2005.

The new Motorsport Center, officially opened last summer but not yet complete, replaces a set of ad hoc buildings known as the "barracks.'' That nickname was derived from both their Spartan appearance and the fact that Porsche helped develop tanks for the German military on the site in the 1960s. Total floor space is now more than 129,000 square ...