Ferrari logo


Great Ferrari Innovations: The E-diff and side slip control

In a world where lap times are everything, the Prancing Horse’s advancement into chassis control and driving dynamics has been game changing
Words - Jason Barlow
Film - Oliver McIntyre

Amongst his many talents, Enzo Ferrari was known for his quick wit and waspish comments. He would surely have enjoyed social media…

Anyway, he once famously noted that a Ferrari client was buying the engine and the rest was thrown in for free.

These days the engine, whilst still the beating heart of a Ferrari, is just one part of a furiously complex network of components and algorithms. In particular, the work Ferrari’s magicians have done on chassis control and driving dynamics has to be experienced to be believed. 

The E-diff arrived in 2004's F430 and is a prime example of a technology migrating from Formula One to a road car 

Where to start? Perhaps with the E-diff, which arrived in 2004’s F430 and is a prime example of a technology that migrated from Formula One to road cars. What does it do? Enhances high speed roadholding by optimising the amount of grip available during cornering while reducing loss of traction. 


How does it work? By distributing torque between the wheels using two sets of friction discs controlled by a hydraulic actuator; the amount of torque transmitted is dependent on variables including steering angle, throttle pedal input, and yaw (the rotation of a vehicle about the vertical axis). 

Watch the story of “E-diff” and “side slip control” and their effect on the car dynamics

Lap times around Fiorano are a barometer for progress in Ferrari’s cars: the F430 laps the track three seconds faster than its predecessor, the 360 Modena. That’s a testament to the confidence the driver has in the car’s responses. Confidence is key. But electronics are important, too. 


Since then, the trajectory has been astonishing, a new paradigm established in which the hardware is truly elevated by the software. Ferrari’s track-oriented cars tend also to be the test-beds for the latest tech, and 2008’s 430 Scuderia remains a highpoint for many fans and clients. 


The fact that Michael Schumacher was heavily involved in the car’s development means it’s liberally sprinkled with magic dust, but the E-diff was also reworked to embrace the F1-trac traction control system from the 599 GTB. 

The 430 Scuderia's E-diff was reworked to embrace the 599 GTB's F1-trac traction system    

Actually, this wasn’t about ‘control’: this was traction ‘optimisation’. With the car’s manettino in ‘race’ mode, the 430 Scuderia gives the driver total belief on entry and apex, minimising understeer and maximising feedback, while the E-diff and traction system jointly and seamlessly deliver a full-blooded, full-throttle corner exit. 

To contemporary road testers, it was so good it felt almost surreal. It also felt like a pivotal moment in Ferrari road car evolution. And so it proved. Next up was the 458 Speciale, the last and most powerful normally aspirated mid-engined V8 Ferrari, and another in that fabled track-oriented blood-line. 

The 488 Pista uses Side Slip Control, combined with the Ferrari Dynamic Enhancer, which brings the brakes into play 

But it was also the first Ferrari to use the SSC, or side slip control, whose algorithms effectively compared the angle of the car with the angle of the corner, and in tandem with the E-diff and F1-trac juggled all the variables in minuscule fragments of time to push the dynamic boundaries even further. This car is one of the all-time greats: as organic as it is high tech. 


Purists can be sniffy about anything that seemingly interferes with the sanctity of the driving experience, but Ferrari’s innovation in this area simply ticks so many boxes it’s irrefutable. The chassis electronics have become so well calibrated that even a highly competent driver would concede that on-the-limit driving is more satisfying as a result. 


It also helps that the interventions are imperceptible. Crucially, the tech opens up the car’s dynamic bandwidth to a larger number of clients, whilst improving the margins of safety. And it even allows the less naturally talented driver to maintain a respectable oversteer slide (or drift, to use the more YouTube-friendly vernacular) without spinning off. 

The track orientated  Ferrari 430 Scuderia remains a highpoint for fans and clients alike 

The 488 GTB, F12tdf and 488 Pista all use evolved versions of Side Slip Control. The Pista also added another tool: the Ferrari Dynamic Enhancer, which brings the brakes into play. This system predicts a moment of yaw based on the SSC’s algorithms and works with the dynamics ECU to determine how much brake pressure is needed at each wheel. It’s complex stuff, no question, but the end result is a sense of dynamic harmony. It’s also wildly exciting to drive. 


And yet Ferrari raises the bar with each new model. Perhaps the greatest statement of intent is made by the SF90 Stradale, the company’s current range-topper. As a hybrid, it brings a whole new set of possibilities into the frame, all of which had to be meticulously networked. 


These include the high-voltage system controls (including the MGUK, battery and inverter), the engine and gearbox, and the vehicle dynamics set-up. Welcome, then, the new eSSC – electronic Side Slip Control – which governs the regulation and distribution of engine torque to all four wheels across three key parameters.


This includes traction control, brake-by-wire (the braking torque needs to blend the force from the regular hydraulic system with that from the e-motors), and torque vectoring, which manages the forces on the outside and inside wheel during cornering for maximum traction. 


It’s heady stuff, no question. But make no mistake: whatever your view on algorithms and their role in the modern world, they have been transformative when it comes to the way a Ferrari handles.