After watching the last Best Motoring volume I would say that the main factor in that amazing lap time is Suzuki's driving. In this video, T. Kinoshita, a Japanese touring car champion who has competed several times at the 24h of Nurburgring (this year in the Lexus LF-A, for instance) does some fast laps in a LHD Spec-V whose transmission overheats and then tries again in a RHD Spec-V achieving a fastest laptime of 7:34.46 suffering some overheat problems again at the end of this lap. Anyway, aside from those problems, you can see that Suzuki really extracts everything that is possible from that machine, making other drivers look a liitle bit sloppy behind the wheel of the GT-R.