The new Carrera GT has set a new lap record for road going cars on road tyres round the Nürburgring for a German Magazine.
The time set was 7.32.44, in the article Porsche say that these times until recently, where only set by Prototypes, and until the 956 came along this seem true.
I have looked at found the the fastest lap in 1981 was 7:33,530 set by a Porsche 908/80 (936) and in 1982, 7:23,870 set by a C100.
In 83 the last WEC round, the record was a stunning 6:25,910 set by Bellof in a 956.
In 1980 935k3 took about 7:34 to get round
In 1971 A Ferrari 312 took 7:40,800
I think I might order one.