Audi wants to get the most out of the diesel technology it developed for the now-defunct R10 Le Mans racer. It's dropped the engine into the Euro-only Q7 V12 TDI and is possibly installing it into a version of the R8, but that still might not be enough. Now Audi is rumored to be loaning the engine to its upper-class cousin for the next generation of the Bentley Arnage.

At this point nothing surprises us from Bentley. The company has been long-rumored to be considering diesel technology, and its engine choices have been anything but conventional. It's even been rumored that Bentley has tried to stuff the W16 engine from the Bugatti Veyron into the next Arnage.

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