All eyes on Le Mans 24h

By Steven De Groote on 11 Jun 2015, 00:18

Race event, Le Mans 24h, Circuit de la Sarthe

Impressive competition and close encounters at the World Endurance Championship races at Silverstone and Spa-Francorchamps have set the scene for this weekend's Le Mans 24 hours race.

The epic and arguably toughest race challenge in the world is again set to take place this weekend at Circuit de la Sarthe, France where the 83rd edition of the 24 hours race will be run as of Saturday 15:00h local time.

Once again, Audi are strong contenders for this year's win, backing on the experience of the last 15 years, during which the German manufacturer managed to take 13 race wins, interrupted only by Bentley's win in 2003 and the Peugeot 908 HDi FAP in 2009. After a difficult year in 2014, during which Toyota clearly had a power advantage, Audi has stepped up and improved on the weaknesses of its 2014 contender.

The new R18 e-tron quattro features a 4MJ energy recovery system, based on a flywheel sitting aside of the driver's seat. Audi claims developing its single unit flywheel from 2MJ to 4MJ worked out as the better solution compared to adding another unit and immediately move up to a 6MJ energy recovery unit. All this unit's power is recovered from and pushed back into the front wheels, whereas the engine itself drivers the rear wheels.

The Porsche challenge

Porsche however looks ready to put up a considerable challenge, having returned to WEC in 2014. The Porsche 919 Hybrid has already shown its worth at Spa-Francorchamps where it was seen to be considerably more powerful in the rise up on the famous high-speed Raidillon corner.

The car is equipped with a 2-litre V4 turbocharged petrol engine with an output of more than 500 hp, which powers the rear axle, and an electric motor with over 400 hp that drives the front wheels and gets its electricity from two energy-recovery systems. A liquid-cooled lithium-ion battery temporarily stores converted braking energy from the front axle as well as converted exhaust-gas energy. The reworked drive system is more powerful and more efficient than before. The Porsche 919 Hybrid was homologated for the top energy-recovery category (8MJ for one lap in Le Mans) for the first time in 2015.

Up next

The third main contender in the main LMP1 category, Japan's Toyota has seemingly dropped down the pecking order and pace-wise did not match Audi or Porsche in the first two WEC races of this year. Updates include aerodynamics, revised front end including crash structure and new suspension kinematics to optimize tyre usage, plus additional weight saving. The TS040 Hybrid will again feature a 6MJ energy recovery system based on super capacitors, which together with the 3.7 litre, 90° V8, naturally aspirated engine provides more than 1000hp.

Fourth up is Nissan's GT-R LM Nismo, which contrary to the other LMP1 cars features a front mid-engine layout. The engine, co-developed by Nissan and Cosworth, is a 3.0 litre 60° V6 with dual turbochargers and direct injection, and is seen by Nissan as the most fuel efficient design. It's said to be good for around 500hp.

Behind the engine and beneath the cockpit is a kinetic energy recovery system using two flywheels developed by Torotrak, charging from the front brakes and powered the front, and optionally the rear wheels as well. Given the team's lack of testing however, and the team's first year of running, Nissan is on the back foot and is having trouble deploying all of its 750hp of its hybrid system during the run up for the Le Mans 24h.

First qualifying

The first qualifying practice session immediately confirmed Porsche's apparent dominance, with the three Porsche 919 Hybrid's settings the fastest times of the session. Marc Lieb proved fastest of all in car #18, lapping the circuit in 3:16.887 early on in the session. From 4th to 6th there are the Audis, even though it should be noted that Benoit Treluyer ended up stuck in the gravel twice while complaining of an unpredictable balance on his car.

Toyota's two TS40's are next in 3:23's, followed 3 seconds further back by the Rebellions. Max Chilton steered the fastest Nissan GT-R LM around in 3:38.468, a few tenths slower than the fastest LMP2, being the KCMG Oreca Nissan.