The LMP1 grid at the FIA World Endurance Championship (WEC) and the 24 Hours of Le Mans welcomes a new entrant today in the shape of the new Nissan GT-R LM Nismo, which joins the Audi R18 e-tron quattro, Toyota TS040 Hybrid and Porsche 919 Hybrid for 2015. This marks Nissan’s return to top-level endurance racing after a 16-year hiatus.
Like the others, the Nissan is a hybrid, but there’s where the similarities end. Firstly, the long bonnet isn’t just there to provide a visual link to the road-going GT-R – there’s actually an engine underneath, a twin-turbocharged, direct-injected 3.0 litre petrol V6, making this the first front-engined Le Mans Prototype since the Panoz Esperante GT-LM from 2006.
Even more interesting is where the internal combustion mill sends its power – to the front. Yes, this is technically a front-engined, front-wheel drive LMP1, although since there’s also a Kinetic Energy Recovery System (KERS) that utilises an even more powerful electric motor to drive both the front and rear wheels, it’s more accurately an all-wheel drive racer.
Total output is said to be somewhere in the 1,250-1,500 hp region – around 500 hp from the petrol engine, and upwards of 750 hp from the eight-megajoule KERS system. A five-speed sequential manual transmission transfers power to the front wheels.
The reason for moving the whole kit and caboodle to the front of the car is something called through-flow aerodynamics. Traditional cars route air around and underneath the car, creating significant drag; on the GT-R LM, it flows straight through.
Clearing out the rear of the car leaves space for two massive air channels that begin behind the front splitter and flows around the narrow hull-like carbon fibre tub and out the back. This reduces aerodynamic drag, which should improve fuel consumption and performance.
This necessitated some blue-sky packaging solutions – the KERS system, for example, is housed under the cockpit, beneath the driver’s legs (meaning that shorter drivers are required, to fit the cramped cabin). Even the electric drive to the rear has to be channeled up and over the air columns through a series of driveshafts and gearboxes to reach the wheels.
The weight, power and downforce bias towards the front mean that the front tyres are quite a bit wider than the rear – 14 inches at the front, nine inches at the rear.
