The annual Wörthersee Tour has become a showcase for outrageous Volkswagen Group concept cars, but not every noteworthy vehicle comes from the VW mothership. This groovy VW bus certainly wasn't, but it may give the factory efforts a run for their money.

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Dubbed the Race Taxi, this bus features the air-cooled flat-six from a 993-generation Porsche 911. Coachbuilder Fred Bernhard also used 993 steering and brakes for the project, while the transmission comes from a 996-generation 911 GT3.

The powertrain is good for 522 horsepower and 558 pound-feet of torque. Yep, this bus should give people quite a shock when it flies by on the highway. Giving a clue to the extensive modifications are its 18-inch BBS wheels and eye-catching paint job complete with racing number.

Some carbon fiber parts help trim weight to 3,307 pounds. It took Bernhard six years to build this Franken-bus, according to World Car Fans. The results show that it was time well spent.

CHECK OUT: New Photos And Video Of 600-Horsepower Audi TT Clubsport Turbo Concept

While the Race Taxi is appealingly retro, VW's own concepts for this year's Wörthersee Tour represent potential future products and technologies. That includes the GTI Clubsport concept--which previews a future production model--as well as the plug-in hybrid Golf GTE Sport. And from fellow VW Group brands, Audi has the TT Clubsport Turbo concept—a hot rodded TT with 600 hp—while Skoda showed the FUNstar pickup truck and rally-inspired Fabia Combi R5.

For more Wörthersee Tour coverage, head to our dedicated hub.

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