The one-second F1 tech gain that made a car slower

In the aftermath of a hugely-successful period in the mid-1990s, the Benetton Formula 1 team endured something of a lean period. This was after its title-winning triumvirate of Michael Schumacher, Rory Byrne and Ross Brawn all exited stage left, swayed by the lure of Ferrari.

Following their collective departures, Benetton won just one more race. Returning from the sidelines after a medically-enforced break, veteran driver Gerhard Berger grabbed a surprise victory at the old Hockenheim in 1997. Back then, the sprawling German venue tended to be something of a charity benefit concert for the most power-laden of cars, and the Renault-powered B197 was sufficiently gutsy enough to carry Berger to a lights-to-flag victory from pole.

Success was sparse after that. Renault left the care of its successful V10 units to Mecachrome, while Benetton's Nick Wirth-designed 1998 car managed just two podiums in the hands of Giancarlo Fisichella. With only one point accrued from the final seven rounds of that championship, the team needed to stop the rot. Having been at the forefront of pushing F1's rules to their limits just a few years before, it was pinning its hopes on a new innovation to fire its way up the field.

Resolving to improve handling characteristics at the front end, Benetton had come up with a novel way to boost turn-in and reduce the chances of locking up the unloaded wheel as the car turned. In essence, the Enstone engineers had developed a front-mounted limited-slip differential - linked to a pair of driveshafts connected to the front wheels.

This was the Front Torque Transfer (FTT) device, and it was developed to suit circuits in which carrying braking into the corners - known as trail braking - was common. Former Sauber and Arrows chief designer Sergio Rinland, then working for Benetton, recalls how the system originated.

"We had the initial beginnings of having a good lap time simulation set-up," Rinland says. "The guy in charge of the programme had the idea of incorporating a differential in the front axle to link the left and right front brakes.

"If one wheel tried to lock, it would transfer the torque to the outside and then you minimise the locking and gain more braking as you're not losing any braking power. When he put it in the simulator, he saw it gave us an extra second a lap around Silverstone.

"When the chief designer at the time saw the lap time generated, he didn't think twice - he said 'we're going in that direction'."

With a conventional differential, the rear driveshafts are encouraged to turn at different rates as a car moves, ensuring that handling is predictable as the inside wheel rotates at a slower velocity. Benetton's engineers figured that, by adding a similar concept to the front, the outside wheel could be made to rotate faster while sustaining a torque transfer effect. This would reduce the chance of a driver enduring a bout of understeer due to a lock-up under braking.

"The guy in charge of the simulation just mathematically put a differential between the front two wheels and nothing else" Sergio Rinland

The system was first tested on a modified Benetton B198, albeit in an unsuitable manner for racing as the FTT was wedged into the crash structure, and the engineers deemed the concept worthy of pursuing for the next car - the B199. Here, the device was nestled next to the steering rack and was mounted as low down as possible to reduce the effects on the car's centre of gravity.

Rather than opting for the lighter properties of a plate differential, which uses the friction between a collection of clutch discs to transmit torque, Benetton required something that could be more easily tuned for the demands of each circuit, and so plumped for the benefits of a viscous differential unit.

With this, whenever the speed difference between the two wheels was too great, the differential could lock progressively. Although the FTT device offered tangible rewards, and reduced the risk of losing time to snatched brakes during an all-or-nothing qualifying lap, it provided plenty of its own baggage as Benetton's engineers were forced to wrestle with compromise.

Having conducted the initial simulations with the effects of the differential in mind, the team crucially failed to factor in changes to the car, and the main caveat was that the device had to be quite large to accommodate these features. This therefore extended the wheelbase of the car.

"This is what the guy in charge of the simulation did," says Rinland. "He took the same car, and just mathematically put a differential between the front two wheels and nothing else.

"The simulated car was the same geometry - same dimensions, the same wheelbase, the same weight, the same everything! When we started to build the real car, we had to make it longer, because we couldn't put the pedals in the front axle, we needed distance to allow the differential so the car became longer.

"With the differential and driveshaft, the length of the chassis and the aerodynamic change from having a longer car, it was a heavier car, and it was difficult to develop the differential."

Regardless, Benetton's technical team felt confident enough that the positive benefits of the system outstripped the negatives, and the cars were packed off to the season opener in Melbourne.

Fisichella got the season under way with fourth place at Albert Park, albeit during an attritional race in which he finished 33 seconds behind winner Eddie Irvine. Nonetheless, Fisichella managed to rack up a smattering of points in 1999, scoring in three of the opening four rounds while his team-mate Alexander Wurz struggled in the other car.

Hit with the weight penalty of the FTT, the tall Austrian - his 6'1" frame dwarfed the more compact Fisichella - was at a natural disadvantage. This gave the Benetton engineers myriad opportunities to scratch their heads as they sought to find a way to accommodate his size.

The car was also proving to be a problem, having been heavily compromised to incorporate the system properly. According to Rinland, the FTT's inclusion actually took performance away from the car; the design factors needed to ensure it worked correctly actually caused a litany of fundamental design problems.

"The concept itself would make an existing car a second faster, but the concept meant a different car" Sergio Rinland

"When we put the car on the ground - and it was very difficult to develop the differential - we lost that second, and maybe another second too because of the weight, size and aero that we didn't consider," he says.

"By making the car longer, we had less weight at the front as the weight distribution moved back, meaning we couldn't put as much downforce at the front wing. If we couldn't have that much downforce at the front we couldn't keep the front tyres, so it was a catalogue of disasters - problems, one after another - that were not considered when the simulation was done.

"The concept itself would make an existing car a second faster, but the concept meant a different car.

"That was an experience, and we learned a lot from those mistakes."

With FTT conspicuous by its absence in Benetton's next car, the B200, the team enjoyed a more improved season without the complexities and issues created by its brainwave. But having not managed to fully develop the system it was unable to dip into the potential rewards on offer.

It took another four years for a similar device to make an impact on the F1 landscape; in 2004, BAR included a similar system into its successful 005 car, helping it on its way to a second-place finish in the constructors' standings that year.

With a far more developed system than Benetton's pre-turn-of-the-millennium efforts, BAR courted controversy as its device made use of multiple hydraulic elements - prompting a switch to a more conventional mechanical system.

But before the end of the season, the FIA had outlawed all future front torque transfer devices, with BAR accepting the ban as protests against the system began to rack up.