BorgWarner DCT for Nissan's GT-R

[T-Type]

Much of the DCT's design was in packaging the unit to fit under the GT-R's floor, and making it a four-wheel-drive transmission without a bolt-on transfer case. The final solution was a rear-mounted transaxle

When supercar-beating performance is the main development bogey, vehicle engineers often embrace new solutions. So it was with Nissan's team developing the all-new 2008 GT-R.

Nearly four years ago, they decided that the GT-R would have a six-speed dual-clutch transmission (DCT) driving a rear-mounted transaxle—a complete departure from the front-mounted gearbox in the iconic Skyline models that preceded the new GT-R. Equally fresh was the decision to go outside for transmission-design expertise—in this case BorgWarner, which partnered with Nissan's keiretsu gearbox supplier, Aichi.

"Nissan's high benchmark for the GT-R aimed at turning very fast laps at the Nurburgring—on par or faster than any production car," recalled BorgWarner Program Manager Keith Martin. "To achieve this, and handle the super-coupe's 434 lb•ft (588 N•m) and 480 hp (358 kW), their vehicle-dynamics people decided they needed a 50:50 weight distribution, which meant putting the transmission in the back between the two seats." (For details of the GT-R's turbocharged V6, see January '08 AEI.)

Nissan's GT-R team also specified fast-shifting automatic functionality, rather than the pure manual shifting used before.

"But they didn't want to be saddled with a torque converter and a traditional planetary automatic," noted Bob Blakely, BorgWarner's Manager of Market Research and Planning. "And being a low-volume car, they wanted a single transmission for the entire product line. So Nissan decided it was time to jump into dual clutch."

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