Multi-Station Supercar
Kazutoshi Mizuno is the former head of Nissan's Daytona and Le Mans racing program and a notable exception in the vast bureaucracy of Japanese auto manufacturing. In a corporate culture that normally divides one hat into many smaller ones, he wears two-and they're both huge. Mizuno is the GT-R chief product specialist as well as the chief engineer. As the former, he devised the GT-R's product concept; as the latter, he made sure it delivers as promised. And boy does it.
"I want [the GT-R] to make supercar performance in all conditions" says Mizuno. In his estimation, the current crop of supercars are designed to perform only in optimal conditions (in the dry, at the track) with an experienced driver behind the wheel. His GT-R concept is the exact opposite: "anyone, anywhere, anytime."
To achieve this "multi-station supercar," Mizuno not only sent the GT-R to Rikubetsu and the Nurburgring, he sent it around the world, to all extremes of temperature and conditions. He also profiled current supercars and noted every aspect of their performance. 'Ring times were of particular interest; Mizuno went so far as to chart supercar MSRP versus Nordschleife lap time-to great comedic effect.
"There is a strong correlation between the two," deadpans Mizuno, "so based on its performance, our GT-R should cost over 45 million yen!"
To create the performance of a $400,000 supercar, Mizuno started with an all-new PM (premium-midship) chassis. Distinct from the FM (front-midship) configuration of such rear-drive Nissans as the 350Z and Infiniti G35, the PM chassis features an independent-transaxle-based all-wheel-drive system. Sending engine output to a rear-mounted transmission is believed to be a first for a front-engine all-wheel-drive production car due to cost and complexity (it needs two driveshafts), but there are key advantages. The first is better weight distribution; a transaxle layout puts more weight over the rear tires and helps the GT-R achieve near 50:50 weight distribution under acceleration. At rest the ratio is more like 53:47.
The precision geometry of the transaxle design has another advantage. Mizuno's team engineered one degree of crankshaft tilt from front to rear that becomes zero degrees under acceleration. This means it's a straight shot from engine to rear diff, reducing wasted output. In addition, a carbon-fiber driveshaft is used to reduce not only weight but NVH as well.
The transaxle setup also sets up the GTR for a new dual-clutch transmission and AWD system. Similar to other systems on the market, the GT-R's twin-clutch transmission features six forward gears that can be manually engaged via steering-wheel-mounted paddles or a console-mounted shifter. Nissan claims Formula-1 shift speeds-as quick as 0.2 second in "R" mode.
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