Just days after a Ferrari exec confirmed a hardcore variant of the LaFerrari was in the works come these spectacular spy shots of an 'XX' experimental prototype lapping the Nurburgring. Following the Enzo-based FXX and the Fiorano-based 599XX, the LaFerrari XX is the latest extreme Prancing Horse to emerge from Maranello. According to eyes on the ground, the customer development prototype lapped the Ring in around 6:35.

That would make it the fastest car based on a production model (i.e. not street legal car) to lap the German circuit. The Pagani Zonda R is the current holder of that lap record with a time of 6:47.50. As the LaFerrari's hybrid powertrain produces 950 hp and 663 lb-ft of torque, there wasn't much scope for squeezing out any more performance. Instead, engineers have focused on revising the suspension for the track, improving aerodynamics, and tuning the electronic stability and traction systems. Weight-saving measures – in the form of carbon-fiber body panels the unpainted model can be seen wearing – and slick tires will also help push the car to the absolute limit.

All 499 units of the LaFerrari have been sold, and Ferrari plans to add a couple of dozen units to that number with the XX variant. Kept and maintained by Ferrari, XX cars are rolled out at various race tracks around the globe where owners – typically Ferrari's most loyal customers – get to provide feedback to engineers. The LaFerrari XX will be ready for launch in 2015.