I don't follow this stuff very close Craig. This video was posted at the corvette forum I frequent. The racer types who follow this are saying it's a new "regular production" car record. Again, I don't know what that means. One of them also posted this (I do not vouch for its accuracy or know where it came from.

6:48 Radical SR8 LM Michael Vergers 19 August 2009 Radical Sportscars[1][2][3]

6:55 Radical SR8
Michael Vergers 28 September 2005 Radical Sportscars[4] Timed by Sport Auto [5][6][7]

7:11.5 Gumpert Apollo Speed Florian Gruber 13 August 2009 Sport auto (Germany) (Article)

7:14.89 Donkervoort D8 RS
Michael Düchting 2006 Sport auto (Germany) (Article)

7:18 Porsche 911 GT2 RS
Timo Kluck April 2010 [7] [8] Manufacturer claim.

7:18.1 Donkervoort D8 RS
Michael Düchting 24 October 2004 Sport auto (Germany) (Article)

7:19.63 2012 Corvette ZR1

7:22.1 Dodge Viper ACR (2009)
Tom Coronel
18 August 2008 Chrysler and Motor Trend conducted test.[9]

7:24 Porsche 911 GT2 RS
Horst von Saurma
Sport Auto (11/2010)[10]

7:24.22 Nissan GT-R (2011) Toshio Suzuki
1 October 2010 Nissan conducted test.[11] Semi-wet conditions. Video confirmed. Best Motoring (12/2010).[12]