The hardcore track-focused version of Ferrari's 599 Fiorano, the 599XX, has been spied testing at the Fiorano test track.
The 599XX gets a retuned version of the 599's V12 engine, with its rev limit boosted to 9000rpm and its weight reduced by the adoption of a new crankshaft and more extensive use of carbonfibre in ancillary parts.
Although confirmed details are scarce, Ferrari says it "achieved its goal" of just under 700bhp at 9000rpm.
The power is transmitted through a new version of Ferrari's robotised manual gearbox that features shift times of just 60ms. Ferrari claims that the 599XX can lap its Fiorano test track in 1m 17sec, less than a second off the time of the Enzo-based FXX that it will replace.
The most obvious external alterations to the regular 599 are a variety of carbonfibre additions, including a small roof spoiler, carbonfibre brake disc covers and a enormous carbonfibre undertray and rear diffuser.
Inside, the cabin has been stripped out to race specification, with a bare dashboard and carbonfibre cladding. It does feature a display screen, however; it's used by Ferrari's 'virtual car engineer', which provides instantaneous data on the vehicle's efficiency.