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Unleashed Porsche 919 Hybrid Evo takes track record at Spa-Francorchamps

An evo version of the Le Mans winning Porsche 919 Hybrid established a new track record at Spa-Francorchamps. Porsche works driver Neel Jani lapped the 7.004 kilometer long Belgian Grand Prix Circuit in the Ardennes mountains in 1:41.770 minutes, beating the previous record by 0.783 seconds that was set by Lewis Hamilton (GB) at the wheel of a Mercedes F1 W07 Hybrid.

Hamilton’s lap of 1:42.553 minutes dates back to 26 August 2017 and secured him pole position for last year’s F1 race. Jani achieved a top speed of 359 km/h (223 mph) and an average speed of 245.61 km/h (152.61 mph) on his record lap that he started at 10:23 hrs. Ambient temperature was 11° Celsius (51.8 ˚F), track temperature was 13° Celsius (55.4 ˚F).

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Porsche 919 Hybrid Evo

This was an absolute fantastic lap—an outstanding drivers’ performance from Neel and the result of great engineering. Today’s track record impressively proves the ultimate performance of the most innovative race car of its time. Our target was to show what the Porsche 919 Hybrid is able to do when we loosen the restrictions that normally come from the regulations.

—Fritz Enzinger, Vice President LMP1

With the 919 Hybrid, Porsche has won the Le Mans 24-Hours from 2015 to 2017 three times in a row as well as the world champion titles for both, manufacturers and drivers, in the FIA World Endurance Championship (WEC) during the same years.

The technical regulations from the FIA for the WEC and Le Mans successfully delivered close competition between the conceptually very different class 1 Le Mans hybrid prototypes entered by Audi, Porsche and Toyota. As a consequence this never allowed answering the question of the full potential of the Porsche 919 Hybrid if it wasn’t chained by the limitations.

It was kind of an engineer’s dream come true for us. Having developed, improved and raced the car for four years, the guys had a very close relationship to it. We all knew, no matter how successful the 919 Hybrid was, it could never show its full abilities. Actually even the Evo version doesn’t fully exploit the technical potential. This time we were not limited by regulations but resources. It is a very satisfying feeling that what we’ve done to the car was enough to crack the Formula One record.

—Stephen Mitas, Chief Race Engineer LMP1

To prepare the record car, the base was the 2017 world championship car. On top came developments that were prepared for the 2018 WEC but never raced after the end of 2017 withdrawal. Additionally, several aerodynamic modifications were made. The entire hardware of the power train remained untouched.

The 919 is powered by a compact two-liter turbocharged V4-cylinder engine (90 degree cylinder bank angle) and two different energy recovery systems: KERS with a motor generator unit (MGU) mounted on the front axle for recapturing brake energy; ERS for recuperation of energy from exhaust gases.

The combustion engine drives the rear axle while the electro motor boosts the front axle to accelerate the car with four-wheel drive. At the same time it recuperates energy from the exhaust system that otherwise would pass unused in to the atmosphere. The electrical energy that comes from the front brakes and the exhaust system is temporarily stored in a liquid-cooled lithium-ion battery with cells from A123 Systems.

The WEC efficiency regulations limited the energy from fuel per lap by using a fuel flow meter. At the 2017 championship round in Spa, in the Porsche 919 Hybrid’s final season, it could use 1.784 kilogram/2.464 liters of gasoline per lap. The V4 combustion engine’s output back then was around 500 HP. Freed from these restrictions, equipped with an updated software but running the regular race fuel (E20), the 919 Hybrid Evo delivers 720 HP.

The amount of energy from the two recovery systems that could be used in Spa 2017 was 6.37 megajoule. This was by far below the systems’ potential. On his record lap Neel Jani enjoyed a full boost of 8.49 megajoule—the e-machine’s output increased by 10% from 400 to 440 HP.

The engineers also unchained the aerodynamics of the 919 Evo from the regulations. The new larger front diffuser now balances the new and very large rear wing, both of which have actively controlled drag reduction systems.

The hydraulically operated systems trim the trailing edge of the front diffuser and opens up the slot between the rear wing main plane and the flap respectively in order increase the aerodynamic efficiency of the Evo.

Underneath the Evo the turning vanes and floor have been optimized with fixed height side skirts to increase the aerodynamic performance again as efficiently as possible. In total the aero modifications resulted in 53% higher downforce and an increase in efficiency by 66% (compared to the 2017 Spa WEC qualifying).

To help further expand the performance envelope, the super-fast Evo gained a four-wheel brake-by-wire system to provide additional yaw control. Furthermore, the power steering was adapted for the higher loads and stronger suspension wishbones (front and rear) were implemented.

Compared to the car in race trim, the dry weight was reduced by 39 kilograms to 849 kilograms. To achieve this, everything was removed what isn’t needed for a single fast lap: air-conditioning, windscreen wiper, several sensors, electronic devices from race control, lights systems and the pneumatic jack system.

Porsche’s multi-year tire partner Michelin was immediately interested to work with a car that produces more downforce than a Formula One car. Keeping the tire dimensions (31/71-18), the target was to increase the grip level significantly. Michelin developed new compounds to deliver the necessary grip with no compromise on safety.

The record lap at Spa was the first appearance on the 919 Tribute Tour. It will next do a demo lap on the legendary Nordschleife before the start of the 24-Hours Nürburgring race on May 12. Drives at the Goodwood Festival of Speed (12 to 15 July) and the Festival of Porsche in Brands Hatch (2 September) will follow as well as the car’s participation at the Porsche Rennsport Reunion in Laguna Seca, California (26 to 29 September).

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