The front tires of the 2015 Nissan GT-R LM Nismo have a really hard job. Not only are they tasked with the majority of braking and turning duties like other Le Mans->ke1591 prototype racers, but they also have to put down 1,250 horsepower produced by its twin-turbo 3.0-liter V-6 and flywheel-based energy reclamation system. Despite sounding like a machine designed specifically to vaporize racing->ke447 tires, designer Ben Bowlby says the car is actually relatively easy on its front rubber.

Working with the team at Nissan,->ke62 Michelin has developed a bespoke set of tires, 14 inches wide at the front and just 9 inches wide at the rear. The ratio between the two is the same as the Nismo GT-R’s 65-to-35 front-to-rear weight distribution, which is achieved thanks to the car’s unusual front-engine layout. It’s a weird setup, but Nissan anticipates the fronts will last two to three fuel stints at Le Mans, which is more or less on par with other P1 teams. Crucially however, the rears can last up to nine stints because they have so little work to do. That means the rears may only need to be replaced three or four times over the course this year’s entire 24-hour race, saving an estimated 24 seconds per pit stop.

The unusual setup also allows for some interesting aerodynamic features, which Nissan hopes will give it an advantage. The lack of an engine in the rear creates room for two “tunnels” that run the length of the car on either side, allowing air to flow through the GT-R LM rather than around it. This is enhanced by the rear tires, which, because of their smaller aerodynamic profile, allow for better airflow around the rear bodywork.

So, how’s it working so far? Honestly, not all that well. The fastest of the three Nissans was some 20 seconds off the pace set by the fastest Porsche 919 at this year’s Le Mans test day, and was slower than several P2 cars. We’ll find out if the team learned any new tricks new when the GT-R LM makes its race debut later this week at the 2015 24 Hours of Le Mans.

2015 Nissan GT-R LM Nismo

Read our full review here.