Underneath this heavily-disguised Ferrari mule is the new 700bhp replacement for the Ferrari 599. Spied in the raods around Ferrari's Maranello base, the new model is only weeks away from its official debut at the Geneva motor show in March.

The new supercar will be the most powerful road car in Maranello’s history, possibly producing as much as 700bhp. “If you look at where we went from the F430 to the 458, and from the 612 Scaglietti to the FF, it is not hard to see where we want the next 599 to be,” said one insider close to the project. “We are not looking for a small step.”

Another source said it would be very surprising if the car did not have “at least” 700bhp. Given that the FF motor is now rated at 651bhp, a clear 120bhp ahead of the 612 Scaglietti, and that the current 599 GTB has 612bhp in standard tune, 700bhp is clearly technically possible.

Read Autocar's first drive of the new Ferrari FF

The new 599 will be powered by the next generation of the direct-injection 6.3-litre V12 used in the FF, an engine based on the original 599/Enzo unit and capable of 850bhp in the FXX Evoluzione.

Ferrari’s new flagship will also feature breakthrough structural and detailed engineering design to ensure that it is lighter than the model it replaces. The shedding of weight has started with the FF, which, despite its all-wheel drive hardware, has an almost identical kerb weight to the 612 Scaglietti’s.

Read the first drive of the new Ferrari 599 GTO

These weight savings will have to be delivered by Ferrari’s alloy monocoque body and not carbonfibre, which has been the route pursued by Lamborghini and McLaren. “The story of aluminium is not yet told,” said our source. Ferrari believes that carbonfibre is not yet suitable for the kind of volume production required for the 599 replacement.

Ferrari has also hinted very strongly that the 599 will stick with a rear-drive layout. The company sees its new four-wheel drive system as “best suited to our grand touring cars”, a category that doesn’t include the 599. However, Ferrari is on the record as saying that the system is destined for more than one car, with the next-generation California being the most likely recipient.

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