Two Scirocco GT24-CNG cars with natural gas engines as well as three Scirocco GT24 vehicles using conventional petrol fuel will take on strong rivals in the "Green Hell”. The aim is to add another victory to those clinched in the highly competitive class for two-litre turbo engines in 2007 and 2008 and, in addition, to be successful in the class for alternative powertrains, thanks to EcoFuel natural gas technology.
"The 24-hour race is a very special challenge. The Nürburgring-Nordschleife is more difficult than any other track, the field is huge and the race a real marathon,” says Volkswagen Motorsport Director Kris Nissen. "Volkswagen sets standards on the road with its EcoFuel natural gas models and we want to show that alternative powertrains like CNG technology can be successful in motorsport as well. In addition, we want to achieve the hat-trick with our petrol-powered Scirocco GT24 in the class of vehicles with two-litre turbo engines.”
Volkswagen EcoFuel: additional powertrain concept for the proven Scirocco GT24
The five Scirocco GT24 cars are powered by proven as well as by innovative technology. The two-litre turbo engine used in the three petrol-powered Scirocco cars is almost identical to last year's version, with one exception. An air restrictor with a smaller cross-section prescribed by the regulations reduces the engine's power output from 325 to 315 hp. The EcoFuel engine in the two natural gas-powered Scirocco vehicles generates 282 hp from the gaseous CNG (compressed natural gas) fuel. The engineers primarily focused on the mixture formation of the engine fitted with a turbocharger as well as the balance between maximum exhaust gas temperature and full usage of the turbocharger's potential in order to match the "sister car's” good driveability, high performance and high reliability.
The further development of the chassis and bodywork was focused on detailed aspects as well. Improved weight distribution, an optimised gearbox and aerodynamic fine-tuning characterise the sport coupe for the 2009 endurance classic. "The objective was to reduce overall weight, lower the centre of gravity and, as a result, improve the car's handling,” says Andreas Lautner, Technical Director at Volkswagen Motorsport. "We achieved this goal and are now at the minimum weight of 1,100 kilograms.” In addition, tests on the Nordschleife as well as three races in the Endurance Championship Nürburgring served to systematically prepare for the 24-hour marathon.