Ferrari is extending its FXX programme for another two years, with a new, faster, more developed version of its Enzo-based supercar.In case you're not one of the 20 super-rich owners of an FXX, here's a reminder of what the FXX programme is all about.Created in 2005, the FXX is a track-only car based on the Enzo and with a 6.2-litre V12. It is not homologated for road use, and nor is it designed to compete in any track events. Those who buy an FXX essentially buy themselves a seat on a special research and development programme. Only 20 'client test drivers' can take part, each getting the opportunity to compete in six specially arranged FXX track events a year over the next two years. They can also arrange extra track time in their FXX with Maranello. Initially planned to run for two years, the programme has now been extended as Ferrari has introduced a range of revisions for the car, now dubbed the FXX Evoluzione.The FXX Evoluzione is marked out by a new livery and revised rear wing. The 6.2-litre V12 has been upgraded to produce 848bhp at 9500rpm (1000rpm higher than before), and revisions to the gearbox cut the shift time from 80 milliseconds to just 60 milliseconds.The FXX's traction control now has nine driver-controlled settings, or can be switched off entirely. The suspension and brakes have also been modified.And the price of helping Ferrari develop its cars? It's not the sort of thing they like to discuss. But you will get to drive alongside (or more likely behind) seven-times F1 world champion Michael Schumacher.