New year, new rules

How the 2017 cars have taken shape

The first major technical shift of the hybrid F1 era is designed to make cars faster by up to five seconds per lap. Here are the key points

Want some properly big Formula 1 numbers? You need to rewind by more than a decade. During the first phase of qualifying for the 2004 Italian Grand Prix at Monza, Juan Pablo Montoya topped the times with an average lap speed of 162.95mph in his Williams-BMW. Last year, Lewis Hamilton’s 159.72mph was sufficient to take pole – not a significant drop-off, but scarcely a barometer of progress. In 2005, the final year of F1’s V10 era,  Kimi Räikkönen’s McLaren-Mercedes was quickest through the Monza speed trap during the race, at 229.969mph. The 2016 equivalent? Valtteri Bottas, Williams-Mercedes, 215.989mph.

It’s not just the absolute qualifying numbers, either. For a few years now, drivers have spent much of their time driving to a controlled pace for the sake of tyre conservation – and in the process they have rarely unleashed their cars’ true potential on Sunday afternoons. Consider the 2015 Spanish GP, when Sebastian Vettel’s fastest race lap would have put him 17th on the grid for the supporting GP2 race… and yet he finished third.

And so, after years of trying to rein in cornering speeds in safety’s name, governing body the FIA has mandated technical rule changes designed to increase them. 

The two key areas affected by the new regulations in design terms are the tyres and bodywork. This year, cars will have a significantly broader contact patch, thanks to tyres about 25 per cent wider than last year. Fronts grow from 245 to 305mm and rears from 325 to 405mm, while diameter is also slightly increased (the cars will continue to run 13-inch wheels). Pirelli estimates that the wider tyres and increased track will on their own account for a lap time reduction of about 2sec. 

Meanwhile, the cars’ overall width increases from 1800 to 2000mm, which permits the incorporation of a wider, more effective front wing (1800mm, rather than 1650) mated to a longer nose section. Rear wings will be lower (previously 950mm, now 800), as well as 150mm wider and mounted 200mm farther back. Completing a package that is designed to generate greater downforce, diffusers will be higher, wider, longer – and significantly more powerful. Sidepods are chunkier, too, with maximum permitted width being stretched from 1400 to 1600mm. It is anticipated that the extra downforce will, like the wider tyres, also shave a couple of seconds from lap times. To accommodate the cars’ increased dimensions, minimum permitted weight rises from 702kg to 728. 

Other rules have also been tweaked – for example the token system that applied to engine developments has been abolished and traditional safety car stars have been modified – but it is the design changes to the cars themselves that will be most noticeable. 

As ever in Formula 1 where the tolerances are so small, the changes to tyres and aerodynamics will have a significant knock on effect on dozens of other components from brakes, to suspension and fuel efficiency. We asked Neil Oatley, McLaren’s design and development director, to cast his slide-rule over the new regulations and explain how they will affect this year’s cars.

Pitstops

The increased wheel sizes, particularly at the rear, make a fast tyre change more difficult – but practice and developing technique should bring the elapsed time back to where it was without changes to the equipment, other than an allowance for deeper wheel insets.

Battery

Shorter braking distances make the process of recharging and managing the battery more of a headache.

Weight 

The change in regulations causes an unwanted increase in the weight of many components – the minimum weight limit has been increased to cover the known effects – so the challenge of designing to this target should remain similar. As ever, though, new performance ideas can add weight. As the car is less of an evolution than normal years, achieving the regulation weight distribution becomes a little more difficult.

Suspension

With higher downforce levels and increased tyre grip, the loads on all the suspension components are considerably increased – for aerodynamic reasons we will not want the suspension links and mountings to be more intrusive than in previous years, so the suspension designer’s task is made somewhat more difficult – the wider track additionally amplifies the loads at the inboard fixing points, so the tensile and compressive capacity of the composite links are stretched to higher limits – particularly the junctions between composite and metal sections.

Brakes

Greater tyre grip and higher downforce equate to shorter braking distances, which inevitably means higher brake component loads, larger discs and calipers (particularly at the front).

Bodywork

Although the allowable bodywork width has been increased, floors will be built to the limit for downforce generation. We might find that the sidepods remain slim, to provide better flow to optimise the performance of the car’s rear end. With the rear wing becoming lower and wider, the detrimental effects of the downstream flow from the bodywork, most importantly when the car is in a cornering attitude, are considerably more significant than with the previous regulations – careful aero research will be at a premium here.

Rear wing

Over the last few years downforce levels have been very similar at all circuits (ie around maximum), apart from the obvious exceptions such as Monza and Spa. With the much higher base level we will experience in 2017, rear wings will need a much broader range of performance, from simple trimming options to distinct assemblies to suit a given circuit.

DRS 

Because the rear is a much larger device in 2017, the DRS effect will be more pronounced than it has been of late. The FIA will look to learn from the direct experience of running/racing the cars and will adjust the length of each DRS application to a shorter distance, such that the real advantage of using DRS will not be any more significant than it was under the previous rules.

Fuel consumption

Allowable fuel load has been increased by 5kg, which should more or less cover the greater requirement from full-throttle running and drag increase, but it is never an easy target to hit under all conditions.

Drag level

Inherently higher, simply due to the increased dimensions. Cars will be a little slower on the straight – the amount of wide-open throttle around the lap will be higher everywhere, so fuel efficiency will pay dividends.

Steering

For similar reasons to the suspension, the capacity of the power steering system must be raised by a significant margin, but care needs to be taken that sensitivity and feedback to the driver do not deteriorate.

Tyres 

At the time of writing we had still to run 2017 tyres on proper 2017 cars, so the performance, durability, degradation, driveability and ability to follow closely remained unknown.

Sensitivities

This is perhaps the most important aspect of the regulation changes. With larger wings, a more powerful diffuser and large tyres to disturb the airflow, sensitivity to ride height and a car’s attitude in pitch, roll and yaw are all amplified. These are normal tasks that have to be managed, but the consequences of not doing the best job are magnified and thus have a greater effect on car performance, consistency and driveability. This is particularly significant with the front tyres affecting front wing performance and the downstream effect of its wake on the brake ducts, chassis furniture, bodywork and floor/diffuser.

Cooling

With new regulations it’s always a major challenge to provide the requisite heat exchange performance without adversely affecting the aerodynamic efficiency of the whole car – now perhaps more significant with the sidepod width and need for exiting air to have a minimised effect on the lowered rear wing and higher/more effective diffuser.

Rear wing endplate

The lower, wider wing, larger tyres and a more powerful diffuser mean the already complex rear wing endplate will receive an even greater degree of attention to optimise performance.

Overtaking 

This will almost certainly be more difficult than it was in 2016 – the FIA might choose to play with this via DRS.