With a week of car launches already underway, ESPN's technical expert Craig Scarborough highlights the main features to look out for on the new-for-2017 cars.
After the last major regulation change in 2014 failed to capture the collective imagination of F1 fans, 2017's rules are aimed at reducing lap times and improving the visual impact of the series. Formula One's rule makers have prescribed wider tyres, wider cars, more downforce and more horsepower to achieve their aims, but a side effect is that top speeds will be blunted and weight added. However, the overall sum of the changes will be cars that are capable of cornering much harder than they did under the previous regulations.
The details of the changes are far reaching, but in summary the changes can be reduced to a few key areas:
The cars will be 20cm wider and each of the tyres 25% wider, resulting in a lot more mechanical grip.
Both wings are angled differently to previous years and made wider, while the diffuser is larger and the nose longer. All this will add a huge amount of extra downforce.
Perhaps initially understated, the vanes around the chassis, known as bargeboards, can be larger and even more complex. While behind them the floor is wider and leads on to an enlarged diffuser for more downforce created under the car.
While the power units will be rid of the token development restrictions, meaning the engine and hybrid systems can be changed as much as the manufacturers have the resources to do so, the drivers are limited to just four power units per season, which will partly restrict overt development and encourage reliability. Regardless of that, the power units will be delivering nearly 1000bhp when deploying full energy recovery, with some 800-840bhp coming from the fuel-limited 1.6 litre V6 petrol engine alone!
Car developments
Even with such broad changes to the regulations, the areas where teams can add performance are actually fairly limited. The changes largely affect aero and tyres, so it's the bodywork and suspension that will be the key areas to find an advantage.
Every team has spent the winter developing new bodywork and hoping the targets and results they have set themselves are higher than their rivals to give them a competitive advantage. Paranoia and a high rate of development is prevalent in F1, so the cars launched will not show all the details of the designs. Teams will launch their real cars, but some parts will be simple versions of what they will start testing with, some may be modified from last year's car, and some will be missing completely until the cars hit scrutineering in Australia. This makes making real judgements on the car tricky, but the photos and computer 3D renders used at launches will still, at their heart, be the real thing.
Likely traits for the new cars will be ever longer wheelbases and an even steeper angle of rake, although changes to these may not be immediately obvious unless compared to the old cars. It's a common misconception in F1 that a long-wheel base leads to barge-like slow steering, but in fact it purely has an aero effect. Longer wheelbases create more space to direct the air along the car and this year the bodywork rules encourage longer wheelbases to package bargeboards into the space between the front wing and sidepods, so this will be a popular route.
Likewise, the move to a nose-down tail-up attitude, known as a rake, will be even more pronounced for many teams. Running the car with a steep rake angle creates more downforce from the front and in particular the diffuser, with the compromise being a raised centre of gravity and the challenge of sealing the large gap between the car and track. In the past few seasons the level of rake has been limited by the front T-Tray splitter scraping along the track, however the splitter is shortened this year, which allow the front wing to ride even lower with a steeper raked set up.
Looking more at the details, the front wing will continue to dominate the airflow along the car and its complexity remains uncontrolled within its wider span for this year. The aim of the front wing is not solely downforce -- the wing is quite capable of creating enough load to balance the car -- it's also influential in shaping the airflow around the front tyres. With the wider tyres, which will add a lot of drag to the cars, the wing will need to change to reduce the turbulent wake shed from the larger tyres spinning in the airflow. So, it's the outer sections of wing we need to keep an eye on, the way the wing sweeps outwards, the number of aerofoil sections and the shape of the cascade winglets mounted to it.
Sadly, the noses, while longer, are still allowed to have the thumb-like proboscis sticking out of the end. Every team will have their own take on the preferred shape, but while this is an obvious difference, there isn't a lot of performance to be gained from the nose tip. With the longer noses, the airflow over them becomes trickier to manage, so the old Sauber trick of an S-Duct bleeding air from below to above the nose will be common.
The next key area, and one that is sure to explode with wild and potentially unattractive solutions, is the bargeboards. Following a number of elaborate interpretations in 2008, they were simplified in 2009, but by last season teams like Mercedes had added huge complexity to these powerful devices. With wider and longer regulated zone to fit these within, the teams will be changing these at nearly every race as they find over greater airflow control gains from them. So, do not expect to see representative versions on the launch cars, the real ones will be hidden away, even after the first runs in testing.
Adding much of the aero performance of these new cars will be the larger diffuser. Longer, taller and wider, this device creates low pressure under the car and unlike a wing creates very little drag. This free downforce for no top speed impact will be a primary target for the teams. Diffuser development has always been a secretive practice, with teams deploying mechanics behind the car when parked to hide the shapes from prying eyes. With this new generation of diffusers, the detail will be even more important, yet with the bigger opening and higher rear ride height, the diffuser will be even easier to be seen, so expect lots of covers keeping this hidden away.
A lower front wing from a steeper rake angle and more downforce potential from the floor and diffuser means keeping these at the right attitude relative to the track is of paramount importance. It's the job of the suspension to do this, and even after FRIC was banned, suspension development using remote mounted hydraulic elements has grown -- but over the winter the FIA and Ferrari have been querying the purpose of many of these systems. Suspension is primarily to control the car to maintain the tyre contact patch, but a useful secondary function is to control the aero attitude of the car. While this link is unavoidable and thus legal, systems are being used that have little effect on the tyre and wholly an effect an aero. The FIA has long held the view that such systems are not within the regulations and these Hydraulic Pitch Control (HPC) systems will be a point of contention between the teams and the FIA for the early part of the season.
Power Unit
After three years, the downsized hybrid power units have come a long way. With their requisite 66 per cent reduction in fuel consumption, the cars are still racing with as much power as they have ever done. Only the hyper-fueled, super-boosted turbo engines of the 1980s qualified with more power. This fuel restriction has driven incredible efficiencies in combustion technology. You cannot simply produce huge power from a turbo engine without huge fuel flows as this creates a combustion effect known as 'knock' which will soon wreck the engine. Mercedes were first to introduce a new combustion system to run the engine at such lean fuel ratios and Ferrari have followed this pre-chamber technology, where a rich fuel mix is ignited in a separate chamber inside the head, which then flows down to burn the lean fuel mix in the combustion chamber. This technology has the potential to create a lot of power without the heat and knock effects of normal lean running.
Honda and Renault are believed to be late introducing this development but their inability to catch up with pre-chamber tech was largely down to the token development system, which restricted how much updates could be brought to the power unit through each season. Now this rule is gone, these teams will be able to catch up on the major changes to the cylinder head of the engine, but that's not to say that Mercedes and Ferrari cannot also make big changes to their power units to maintain their advantage. Mercedes has the upper-hand on outright power, especially in qualifying, while Ferrari need to find a way to make the pre-chamber fuel injector work well in economy mode and qualifying mode -- a tricky compromise.
The other key change on power units is the turbo architecture. Mercedes were able to develop a split turbo for the first season of the current engine rules in 2014 and gain an advantage as a result. A split turbo places the compressor and exhaust driven turbine at separate ends of the engine, interconnected by a common shaft and by the hybrid unit for the MGU-H. This keeps the exhaust and inlet routing short, the hot turbine away from the cool running compressor and slims the rear end of the engine. This isn't a silver bullet solution, it has some installation compromises but appears to be the preferred route in F1. Thus, Ferrari are likely to follow this route and Honda are likely to rationlise its installation, leaving a question mark over Renaults 2017 installation.
Lastly the bane of many fans' enjoyment of the sport in recent years is the engine noise. No changes have been made to the exhausts, so no step change is likely in the audible range of the exhaust. However, the engines are being pushed harder with increases to the volume and the new owners of the sport may make more efforts to reposition the on-car microphones and tune the audio feed to bring the sound to the fore.