Mythbusters: All-Wheel Drive

All-wheel drive has numerous applications. Originally the preserve of off-road vehicles that needed extra traction on tricky terrain, its value in terms of enhancing a car’s dynamic bandwidth soon became clear. The FF, Ferrari’s first all-wheel drive production car, arrived in 2011, and now both the triple Le Mans 24 Hours-winning 499P and F80 use an electrified front axle to deliver unprecedented handling response.

A gripping story – click to watch Ferrari’s history of all-wheel drive

In fact, Ferrari had been experimenting with all-wheel drive for years, the 408 4RM – ruote motrici – cars among the most notable of the company’s concepts. It’s said that Ferrari’s technical director, the late Mauro Forghieri, often pondered the possibility of all-wheel drive in Formula One, but by the Eighties it was the dominant technology in the hugely popular World Rally Championship. Japanese car companies were also experimenting with it.

The 408 4RM was powered by a 4.0-litre V8 derived from the 328 model, and two were made; one had a steel chassis, the other a bonded aluminium structure, with composite body panels and a magnesium bulkhead. The 4WD system used a centre differential and hydraulic coupling, for 29/71 torque split front-to-rear. Vice Chairman Piero Ferrari called time on the project in 1991, citing the system’s extra weight as antithetical to Ferrari’s core engineering philosophy.

Ferrari's AWD experiments began with the 408 4RM concept

Weight saving was integral to the re-born 4RM system, a highly innovative solution that sat at the heart of 2011’s FF – the acronym stood for Ferrari Four. Its V12 engine was positioned behind the front axle which meant that its engineers could site a second, compact transmission ahead of it. A Power Transfer Unit (PTU) effectively acts as a two-speed gearbox which distributes power to the front wheels, via two electronically-controlled, hydraulic wet multi-plate clutches, with one for each wheel. The front transmission can match the speed of the rear wheels, and torque vectoring distributes power side-to-side.

An ingenious solution, not least because this configuration reduced the amount of hardware needed – there was no centre differential or mechanical link front-to-rear. This meant it weighed about half the amount of a regular four-wheel drive system. It also allowed the FF to maintain a lower centre of gravity, and an optimum weight distribution front-to-rear.

The system’s control electronics were integrated with the E-diff and F1-trac traction control system, and the FF was also the first V12 Ferrari to use the dual-clutch gearbox. Clients would have noticed the addition of an Ice/Snow setting on the steering wheel manettino. The FF’s media launch took place on the snowy mountain caps of the Dolomites, where its capability in the trickiest conditions was amply demonstrated.

The 2011 FF was the first AWD production Ferrari. The GTC4Lusso (shown in blue) followed

The GTC4Lusso (2016) evolved the FF’s formula and increased the power output to 690 cv, but it was the 1000 cv SF90 that truly picked up where the 408 4RM left off all those years ago. This was the first mid-engined Ferrari production car to feature all-wheel drive, a feature that was surely integral to its Fiorano lap time: at 1min 19 seconds, it’s seven-tenths of a second faster than the LaFerrari. It combines a 4.0-litre V8 with three electric motors: one sits between the engine and gearbox, and there are two more upfront driving each of the front wheels.

This hybrid configuration ensures there’s torque fill between gear shifts, torque vectoring to sharpen turn-in and agility, but also to provide all-wheel drive. Staunch adherents of rear drive need not fear: this is a Ferrari with astounding handling capability. And the ability to travel up to 28km in electric mode…

The Ferrari Purosangue adds four doors and increased ride height to the FF and GTC4Lusso formula

The Purosangue may cleave closer to what the market deems a four-wheel drive vehicle to look like, but in fact builds on the foundational work done by the FF and GTC4Lusso. Yes, it rides higher than its predecessors and adds four doors, but dynamically this is every millimetre a true Ferrari. It is front mid-engined, has a rear transaxle, and a power take-off unit that operates a pair of clutches to send power to the front wheels. The all-wheel drive system is very rear-biased, in order to preserve the expected Ferrari dynamism.

The front axle chimes in when the conditions require it for maximum sure-footedness, but never at the expense of driver entertainment.

The F80 builds on expertise from the petrol-electric AWD of the SF90 and Le Mans-winning 499P

Ferrari’s commitment to all-wheel drive reaches a zenith with the new supercar F80 , whose 1200 cv power output also sets a new record for a Ferrari road car. This one courses with competition DNA and, like its 499P racing siblings, it has two front-mounted electric motors, an inverter and a cooling system for torque vectoring functionality. A total of 281 cv is sent to the front axle; the inverter weighs just 9kg, and is integrated within it. It’s a packaging and engineering miracle.