The GT-R Nismo will join the Nismo range alongside the 370Z and Juke
Reputedly this particular example featured Nismo-branded engine parts
A prominent rear spoiler was fitted to this test car...
...but it was removed for later test runs
The ride height looks marginally lower than that of the standard GT-R
Giveaway signs that this is a Nismo model include appropriately branded alloy wheels
The standard GT-R features a 3.8-litre twin-turbocharged V6
It's thought that the Nismo version will benefit from some upgrades, raising its power over the standard model's 542bhp
The rear of the car now features two additional ducts, located just above the exhausts
The standard GT-R is capable of 0-62mph in just 3.0sec
It's expected that the Nismo will be unveiled later this year, at the Tokyo motor show
The GT-R Nismo is expected to go on sale in 2014
Former Formula 1 driver Sébastien Buemi is posied to set a new lap record for the Nissan GT-R at the Nurburgring this week.
Track insiders have reported that Nissan has booked exclusive use of the venue for its laps. The current fastest verified time for a Nissan GT-R at the circuit is 7m 18.6sec, set by Toshio Suzuki in 2012. That is the ninth fastest time by a road-legal car at the circuit.
The Nissan GT-R Nismo is expected to be officially revealed at this year's Tokyo motor show in November. It's understood that it is being co-developed with the Williams F1 team in a bid to improve its aerodynamic performance.
"I've done done testing on the Nordschleife and its been interesting," said Buemi earlier this year. "The programme is still at an early stage but we are getting more out of the car all the time. The lap time is coming down all the time, but we don't know what's possible yet."
Previously the car had been photographed undergoing testing outside Nissan's technical centre in Europe. Despite being heavily camouflaged, it was clear that the car had received cosmetic and aerodynamic tweaks, most likely including a Nismo-specific bodykit.
Other changes include a slightly different air intake system, as well as Nismo-specific parts such as alloy wheels.
It also appears that the Nismo variant benefits from a different suspension setup, since it appears to sit slightly lower than the conventional GT-R.
Carlos Ghosn, CEO of Nissan, said: "It would be unthinkable for us to develop a range of Nismo road cars without including the GT-R.
"The standard road car is a global supercar and the GT-R's performance on track reflects the passion and talents of the Nismo team. The GT-R Nismo will be special."
Nissan's standard GT-R, which is powered by a twin-turbocharged 524bhp 3.8-litre V6, is capable of 0-62mph in 3.0sec. It's expected that the Nismo will be faster - but to what extent has yet to be ascertained.
The new Nissan GT-R Nismo is expected to go on sale in 2014, and will be offered alongside the standard version in specialised dealerships. A significant price hike is expected over the standard model, which currently costs £76,610.
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Lewis Kingston/Jim Holder