Two days before the official Prologue for the FIA World Endurance Championship (WEC) at Paul Ricard, France, Porsche presented their new 919 race car for this season. Strong development characterizes the new 919 Hybrid’ technology. The powertrain became even more efficient, the aerodynamics are more specific for the various race tracks and the weight of various single components were reduced.
“The over 900 hp strong Le Mans Prototype is ready for the title defense,” said Fritz Enzinger, Vice President LMP1.
Even the livery of the Porsche 919 Hybrid’s third generation represents an evolution
In its debut year, 2014, the 919 was white and sported the claim “Porsche Intelligent Performance”. The first letters of this slogan were also on the 2015 racing cars with their background colors of white, red and black. In 2016, all three colors are combined into a new design.
Also new are the car numbers
In 2015 Porsche took both first and second at the 24 Hours of Le Mans. In doing so, Porsche won the manufacturers’ World Championship title. In addiiton, Timo Bernhard, Brendon Hartley and Mark Webber became the Drivers’ World Champions and will now race with the number 1 on their car. The sister car of Romain Dumas, Neel Jani and Marc Lieb will carry the number 2.
The most important features of the new 919 Hybrid at a glance:
- For the first time Porsche will deploy three different aerodynamic packages, ensuring the car has the best set-up for their respective race tracks. Three aerodynamic specifications are the maximum allowed by WEC regulation.
- The weight of the four-cylinder turbo engine, as well as its fuel consumption, was further reduced.
- The two energy recovery systems of the hybrid drive have been improved in terms of efficiency. For 2016, the components of the electric drive have become even more powerful and efficient. This applies to the optimized electric motor at the front axle, the power electronics and the new generation of lithium-ion battery cells in the in-house developed battery.
- A new front axle allows for more set-up options, while the intense tire development with partner Michelin made a refined overall set-up for the new 919 Hybrid possible.
The 2016 Porsche 919 Hybrid in detail:
For the 2016 Porsche 919, the basis of the chassis structure remains unchanged, as does the hybrid drive concept (other than the efficiencies mentioned above) with its two-liter V4 turbocharged petrol engine and the two different energy recovery systems (braking energy from the front axle and exhaust energy). Right from the start, for the 2014 season, Porsche had this courageous and spot on concept in place. But the first car showed exceptional potential, especially in terms of weight, and is why a new car for 2015 was built. For 2016, there is less need to change and Porsche is benefiting now from stability for the concept.
The WEC regulations back the hybrid:
The regulations for the LMP1 category require manufacturers to use hybrid drive systems and establish a direct link between performance and energy efficiency. This means that a large amount of energy from recovery systems may be used, but entails a proportional reduction in the permitted amount of fuel per lap. The quantity of fuel consumed in each lap is counted.
The WEC allows engineers a great degree of freedom in terms of the hybrid drive concepts. The teams can choose between diesel and petrol engines, naturally aspirated or turbocharged engines, various displacements, and one or two energy recovery systems. This formula puts the focus on innovations with high relevance for future production sports cars – and this was the main reason why Porsche decided to return to the world of top level motor racing.
V4-turbo with direct injection:
The combustion efficiency and mixture preparation of the 2-liter V4 turbocharged petrol engine, driving the rear axle, was further increased in close work with the engineers from production development in Weissach. In addition, the 90-degree V-engine shed even more weight. Last season, the output of the combustion engine was well above 500 hp. But the 2016 regulations stipulate a lower amount of energy from fuel per lap and reduce the maximum fuel flow for prototypes. In this way, the regulations prevent the LMP1 cars from becoming increasingly faster, yet at the same time act as a catalyst for the engineers’ efforts to generate more power from increasingly less fuel. For the 919, this means around 8% less fuel and power. In other words: ten megajoules less energy per Le Mans lap from the fuel. That costs about four seconds for every 13.629-kilometre Le Mans lap. Perhaps, more importantly, due to these new restrictions, the combustion engine has dropped to below 500 hp.
Two energy recuperation systems:
The kinetic energy produced at the front axle when braking is converted into electrical energy. The second recuperation system is installed in the exhaust tract, where the exhaust-gas stream drives a second turbine in parallel with the turbocharger. It uses excess energy from the exhaust pressure that would otherwise escape into the environment. The VTG technology used here – that is, the variable adaptation of the turbine geometry to the level of exhaust pressure – drives the turbines, even at low engine revs and low pressure. The additional turbine is connected to an electric generator. The electricity produced – along with that generated by the KERS at the front axle – is temporarily stored in lithium-ion battery cells. When the driver calls up the full-boost, additional power output of more than 400 hp will thrust him back into his seat. This power is applied to the front axle by the electric motor, and it temporarily transforms the 919 into an all-wheel drive car with full system power of around 900 hp. For each circuit, the team works on developing the strategies for when and to what extent energy is recuperated and called up.
Lithium-ion battery for energy storage:
The WEC regulations allow engineers plenty of scope with regard to the energy storage medium: Initially, the competition used flywheels and ultracaps (electrochemical supercapacitors). For 2016, they are all following Porsche’s lead of lithium-ion batteries. Another important fundamental decision with the 919 Hybrid was the high voltage of 800-Volt – a technology that series developers are adopting in the Mission E concept car.
Proven chassis with high safety margins:
Like in Formula 1, the Porsche 919 Hybrid monocoque is a carbon-fiber sandwich construction that is manufactured as a single unit. The monocoque, combustion engine and transmission as one unit ensure optimal rigidity. While the V4 engine fulfills a load-bearing function within the chassis, the hydraulically operated sequential 7-speed racing gearbox made of aluminum is mounted in a carbon structure. For 2016, the gearbox and gearbox mounting remain structurally identical. The focus for development on the gearbox was on weight reduction.
New front axle, strong tire development:
For even better driving dynamics, balance, traction, grip and set-up options, the Porsche 919 Hybrid received a new front axle and an optimized rear axle for 2016. After intense testing in February, an increase in performance on the part of the Michelin tires is expected.
Efficient aerodynamics for every race track:
Porsche took a three-pronged approach to aerodynamic improvements in 2016. Until now, Porsche settled on a compromise for the season-opening round of the World Championship and campaigned the 919 with lower down-force than would have been ideal for the Silverstone circuit. This compromise was for the sake of the season highlight at Le Mans. The French racetrack with its long straights requires very low drag, which means down force must be limited to what is absolutely necessary. In 2016 the 919 will start the season running a high down force package. It will be tackling Le Mans with an extremely low down force configuration and will have another high down-force package for the following six WEC races. The regulations prohibit more than three aerodynamic configurations per year.